Home Library Learn Downloads Support Community
Sign in | United States - English | |
12 out of 16 rated this helpful - Rate this topic

FileUpload Class

.NET Framework 4

Displays a text box control and a browse button that enable users to select a file to upload to the server.

System.Object
  System.Web.UI.Control
    System.Web.UI.WebControls.WebControl
      System.Web.UI.WebControls.FileUpload

Namespace:  System.Web.UI.WebControls
Assembly:  System.Web (in System.Web.dll)
C#
C++
F#
VB
Copy 
[ValidationPropertyAttribute("FileName")]
[ControlValuePropertyAttribute("FileBytes")]
public class FileUpload : WebControl
ASP.NET
Copy 
<asp:FileUpload />

The FileUpload type exposes the following members.

  Name Description
Public method FileUpload Initializes a new instance of the FileUpload class.
Top
  Name Description
Public property AccessKey Gets or sets the access key that allows you to quickly navigate to the Web server control. (Inherited from WebControl.)
Protected property Adapter Gets the browser-specific adapter for the control. (Inherited from Control.)
Public property AppRelativeTemplateSourceDirectory Gets or sets the application-relative virtual directory of the Page or UserControl object that contains this control. (Inherited from Control.)
Public property Attributes Gets the collection of arbitrary attributes (for rendering only) that do not correspond to properties on the control. (Inherited from WebControl.)
Public property BackColor Gets or sets the background color of the Web server control. (Inherited from WebControl.)
Public property BindingContainer Infrastructure. Gets the control that contains this control's data binding. (Inherited from Control.)
Public property BorderColor Gets or sets the border color of the Web control. (Inherited from WebControl.)
Public property BorderStyle Gets or sets the border style of the Web server control. (Inherited from WebControl.)
Public property BorderWidth Gets or sets the border width of the Web server control. (Inherited from WebControl.)
Protected property ChildControlsCreated Gets a value that indicates whether the server control's child controls have been created. (Inherited from Control.)
Public property ClientID Gets the control ID for HTML markup that is generated by ASP.NET. (Inherited from Control.)
Public property ClientIDMode Gets or sets the algorithm that is used to generate the value of the ClientID property. (Inherited from Control.)
Protected property ClientIDSeparator Gets a character value representing the separator character used in the ClientID property. (Inherited from Control.)
Protected property Context Gets the HttpContext object associated with the server control for the current Web request. (Inherited from Control.)
Public property Controls Gets a ControlCollection object that represents the child controls for a specified server control in the UI hierarchy. (Inherited from Control.)
Public property ControlStyle Gets the style of the Web server control. This property is used primarily by control developers. (Inherited from WebControl.)
Public property ControlStyleCreated Gets a value indicating whether a Style object has been created for the ControlStyle property. This property is primarily used by control developers. (Inherited from WebControl.)
Public property CssClass Gets or sets the Cascading Style Sheet (CSS) class rendered by the Web server control on the client. (Inherited from WebControl.)
Public property DataItemContainer Gets a reference to the naming container if the naming container implements IDataItemContainer. (Inherited from Control.)
Public property DataKeysContainer Gets a reference to the naming container if the naming container implements IDataKeysControl. (Inherited from Control.)
Protected property DesignMode Gets a value indicating whether a control is being used on a design surface. (Inherited from Control.)
Public property Enabled Gets or sets a value indicating whether the Web server control is enabled. (Inherited from WebControl.)
Public property EnableTheming Gets or sets a value indicating whether themes apply to this control. (Inherited from WebControl.)
Public property EnableViewState Gets or sets a value indicating whether the server control persists its view state, and the view state of any child controls it contains, to the requesting client. (Inherited from Control.)
Protected property Events Gets a list of event handler delegates for the control. This property is read-only. (Inherited from Control.)
Public property FileBytes Gets an array of the bytes in a file that is specified by using a FileUpload control.
Public property FileContent Gets a Stream object that points to a file to upload using the FileUpload control.
Public property FileName Gets the name of a file on a client to upload using the FileUpload control.
Public property Font Gets the font properties associated with the Web server control. (Inherited from WebControl.)
Public property ForeColor Gets or sets the foreground color (typically the color of the text) of the Web server control. (Inherited from WebControl.)
Public property HasAttributes Gets a value indicating whether the control has attributes set. (Inherited from WebControl.)
Protected property HasChildViewState Gets a value indicating whether the current server control's child controls have any saved view-state settings. (Inherited from Control.)
Public property HasFile Gets a value indicating whether the FileUpload control contains a file.
Public property Height Gets or sets the height of the Web server control. (Inherited from WebControl.)
Public property ID Gets or sets the programmatic identifier assigned to the server control. (Inherited from Control.)
Protected property IdSeparator Infrastructure. Gets the character used to separate control identifiers. (Inherited from Control.)
Protected property IsChildControlStateCleared Gets a value indicating whether controls contained within this control have control state. (Inherited from Control.)
Protected property IsEnabled Gets a value indicating whether the control is enabled. (Inherited from WebControl.)
Protected property IsTrackingViewState Gets a value that indicates whether the server control is saving changes to its view state. (Inherited from Control.)
Protected property IsViewStateEnabled Gets a value indicating whether view state is enabled for this control. (Inherited from Control.)
Protected property LoadViewStateByID Gets a value indicating whether the control participates in loading its view state by ID instead of index. (Inherited from Control.)
Public property NamingContainer Gets a reference to the server control's naming container, which creates a unique namespace for differentiating between server controls with the same Control.ID property value. (Inherited from Control.)
Public property Page Gets a reference to the Page instance that contains the server control. (Inherited from Control.)
Public property Parent Gets a reference to the server control's parent control in the page control hierarchy. (Inherited from Control.)
Public property PostedFile Gets the underlying HttpPostedFile object for a file that is uploaded by using the FileUpload control.
Public property RenderingCompatibility Gets a value that specifies the ASP.NET version that rendered HTML will be compatible with. (Inherited from Control.)
Public property Site Gets information about the container that hosts the current control when rendered on a design surface. (Inherited from Control.)
Public property SkinID Gets or sets the skin to apply to the control. (Inherited from WebControl.)
Public property Style Gets a collection of text attributes that will be rendered as a style attribute on the outer tag of the Web server control. (Inherited from WebControl.)
Public property SupportsDisabledAttribute Gets a value that indicates whether the control should set the disabled attribute of the rendered HTML element to "disabled" when the control's IsEnabled property is false. (Inherited from WebControl.)
Public property TabIndex Gets or sets the tab index of the Web server control. (Inherited from WebControl.)
Protected property TagKey Gets the HtmlTextWriterTag value that corresponds to this Web server control. This property is used primarily by control developers. (Inherited from WebControl.)
Protected property TagName Gets the name of the control tag. This property is used primarily by control developers. (Inherited from WebControl.)
Public property TemplateControl Gets or sets a reference to the template that contains this control. (Inherited from Control.)
Public property TemplateSourceDirectory Gets the virtual directory of the Page or UserControl that contains the current server control. (Inherited from Control.)
Public property ToolTip Gets or sets the text displayed when the mouse pointer hovers over the Web server control. (Inherited from WebControl.)
Public property UniqueID Gets the unique, hierarchically qualified identifier for the server control. (Inherited from Control.)
Protected property ViewState Gets a dictionary of state information that allows you to save and restore the view state of a server control across multiple requests for the same page. (Inherited from Control.)
Protected property ViewStateIgnoresCase Gets a value that indicates whether the StateBag object is case-insensitive. (Inherited from Control.)
Public property ViewStateMode Gets or sets the view-state mode of this control. (Inherited from Control.)
Public property Visible Gets or sets a value that indicates whether a server control is rendered as UI on the page. (Inherited from Control.)
Public property Width Gets or sets the width of the Web server control. (Inherited from WebControl.)
Top
  Name Description
Protected method AddAttributesToRender Adds the HTML attributes and styles of a FileUpload control to render to the specified System.Web.UI.HtmlTextWriter object. (Overrides WebControl.AddAttributesToRender(HtmlTextWriter).)
Protected method AddedControl Called after a child control is added to the Controls collection of the Control object. (Inherited from Control.)
Protected method AddParsedSubObject Notifies the server control that an element, either XML or HTML, was parsed, and adds the element to the server control's ControlCollection object. (Inherited from Control.)
Public method ApplyStyle Copies any nonblank elements of the specified style to the Web control, overwriting any existing style elements of the control. This method is primarily used by control developers. (Inherited from WebControl.)
Public method ApplyStyleSheetSkin Applies the style properties defined in the page style sheet to the control. (Inherited from Control.)
Protected method BuildProfileTree Infrastructure. Gathers information about the server control and delivers it to the Trace property to be displayed when tracing is enabled for the page. (Inherited from Control.)
Protected method ClearCachedClientID Infrastructure. Sets the cached ClientID value to null. (Inherited from Control.)
Protected method ClearChildControlState Deletes the control-state information for the server control's child controls. (Inherited from Control.)
Protected method ClearChildState Deletes the view-state and control-state information for all the server control's child controls. (Inherited from Control.)
Protected method ClearChildViewState Deletes the view-state information for all the server control's child controls. (Inherited from Control.)
Protected method ClearEffectiveClientIDMode Infrastructure. Sets the ClientIDMode property of the current control instance and of any child controls to Inherit. (Inherited from Control.)
Public method CopyBaseAttributes Copies the properties not encapsulated by the Style object from the specified Web server control to the Web server control that this method is called from. This method is used primarily by control developers. (Inherited from WebControl.)
Protected method CreateChildControls Called by the ASP.NET page framework to notify server controls that use composition-based implementation to create any child controls they contain in preparation for posting back or rendering. (Inherited from Control.)
Protected method CreateControlCollection Creates a new ControlCollection object to hold the child controls (both literal and server) of the server control. (Inherited from Control.)
Protected method CreateControlStyle Creates the style object that is used internally by the WebControl class to implement all style related properties. This method is used primarily by control developers. (Inherited from WebControl.)
Public method DataBind() Binds a data source to the invoked server control and all its child controls. (Inherited from Control.)
Protected method DataBind(Boolean) Binds a data source to the invoked server control and all its child controls with an option to raise the DataBinding event. (Inherited from Control.)
Protected method DataBindChildren Binds a data source to the server control's child controls. (Inherited from Control.)
Public method Dispose Enables a server control to perform final clean up before it is released from memory. (Inherited from Control.)
Protected method EnsureChildControls Determines whether the server control contains child controls. If it does not, it creates child controls. (Inherited from Control.)
Protected method EnsureID Creates an identifier for controls that do not have an identifier assigned. (Inherited from Control.)
Public method Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method FindControl(String) Searches the current naming container for a server control with the specified id parameter. (Inherited from Control.)
Protected method FindControl(String, Int32) Infrastructure. Searches the current naming container for a server control with the specified id and an integer, specified in the pathOffset parameter, which aids in the search. You should not override this version of the FindControl method. (Inherited from Control.)
Public method Focus Sets input focus to a control. (Inherited from Control.)
Protected method GetDesignModeState Infrastructure. Gets design-time data for a control. (Inherited from Control.)
Public method GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public method GetRouteUrl(Object) Gets the URL that corresponds to a set of route parameters. (Inherited from Control.)
Public method GetRouteUrl(RouteValueDictionary) Gets the URL that corresponds to a set of route parameters. (Inherited from Control.)
Public method GetRouteUrl(String, Object) Gets the URL that corresponds to a set of route parameters and a route name. (Inherited from Control.)
Public method GetRouteUrl(String, RouteValueDictionary) Gets the URL that corresponds to a set of route parameters and a route name. (Inherited from Control.)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Public method GetUniqueIDRelativeTo Returns the prefixed portion of the UniqueID property of the specified control. (Inherited from Control.)
Public method HasControls Determines if the server control contains any child controls. (Inherited from Control.)
Protected method HasEvents Returns a value indicating whether events are registered for the control or any child controls. (Inherited from Control.)
Protected method IsLiteralContent Infrastructure. Determines if the server control holds only literal content. (Inherited from Control.)
Protected method LoadControlState Restores control-state information from a previous page request that was saved by the SaveControlState method. (Inherited from Control.)
Protected method LoadViewState Restores view-state information from a previous request that was saved with the SaveViewState method. (Inherited from WebControl.)
Protected method MapPathSecure Retrieves the physical path that a virtual path, either absolute or relative, maps to. (Inherited from Control.)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method MergeStyle Copies any nonblank elements of the specified style to the Web control, but will not overwrite any existing style elements of the control. This method is used primarily by control developers. (Inherited from WebControl.)
Protected method OnBubbleEvent Determines whether the event for the server control is passed up the page's UI server control hierarchy. (Inherited from Control.)
Protected method OnDataBinding Raises the DataBinding event. (Inherited from Control.)
Protected method OnInit Raises the Init event. (Inherited from Control.)
Protected method OnLoad Raises the Load event. (Inherited from Control.)
Protected method OnPreRender Raises the PreRender event for the FileUpload control. (Overrides Control.OnPreRender(EventArgs).)
Protected method OnUnload Raises the Unload event. (Inherited from Control.)
Protected method OpenFile Gets a Stream used to read a file. (Inherited from Control.)
Protected method RaiseBubbleEvent Assigns any sources of the event and its information to the control's parent. (Inherited from Control.)
Protected method RemovedControl Called after a child control is removed from the Controls collection of the Control object. (Inherited from Control.)
Protected method Render Sends the FileUpload control content to the specified System.Web.UI.HtmlTextWriter object, which writes the content to render on the client. (Overrides WebControl.Render(HtmlTextWriter).)
Public method RenderBeginTag Renders the HTML opening tag of the control to the specified writer. This method is used primarily by control developers. (Inherited from WebControl.)
Protected method RenderChildren Outputs the content of a server control's children to a provided HtmlTextWriter object, which writes the content to be rendered on the client. (Inherited from Control.)
Protected method RenderContents Renders the contents of the control to the specified writer. This method is used primarily by control developers. (Inherited from WebControl.)
Public method RenderControl(HtmlTextWriter) Outputs server control content to a provided HtmlTextWriter object and stores tracing information about the control if tracing is enabled. (Inherited from Control.)
Protected method RenderControl(HtmlTextWriter, ControlAdapter) Outputs server control content to a provided HtmlTextWriter object using a provided ControlAdapter object. (Inherited from Control.)
Public method RenderEndTag Renders the HTML closing tag of the control into the specified writer. This method is used primarily by control developers. (Inherited from WebControl.)
Protected method ResolveAdapter Gets the control adapter responsible for rendering the specified control. (Inherited from Control.)
Public method ResolveClientUrl Gets a URL that can be used by the browser. (Inherited from Control.)
Public method ResolveUrl Converts a URL into one that is usable on the requesting client. (Inherited from Control.)
Public method SaveAs Saves the contents of an uploaded file to a specified path on the Web server.
Protected method SaveControlState Saves any server control state changes that have occurred since the time the page was posted back to the server. (Inherited from Control.)
Protected method SaveViewState Saves any state that was modified after the TrackViewState method was invoked. (Inherited from WebControl.)
Protected method SetDesignModeState Sets design-time data for a control. (Inherited from Control.)
Public method SetRenderMethodDelegate Infrastructure. Assigns an event handler delegate to render the server control and its content into its parent control. (Inherited from Control.)
Public method ToString Returns a string that represents the current object. (Inherited from Object.)
Protected method TrackViewState Causes the control to track changes to its view state so they can be stored in the object's ViewState property. (Inherited from WebControl.)
Top
  Name Description
Public event DataBinding Occurs when the server control binds to a data source. (Inherited from Control.)
Public event Disposed Occurs when a server control is released from memory, which is the last stage of the server control lifecycle when an ASP.NET page is requested. (Inherited from Control.)
Public event Init Occurs when the server control is initialized, which is the first step in its lifecycle. (Inherited from Control.)
Public event Load Occurs when the server control is loaded into the Page object. (Inherited from Control.)
Public event PreRender Occurs after the Control object is loaded but prior to rendering. (Inherited from Control.)
Public event Unload Occurs when the server control is unloaded from memory. (Inherited from Control.)
Top
  Name Description
Public Extension Method FindDataSourceControl Returns the data source that is associated with the data control for the specified control. (Defined by DynamicDataExtensions.)
Public Extension Method FindFieldTemplate Returns the field template for the specified column in the specified control's naming container. (Defined by DynamicDataExtensions.)
Public Extension Method FindMetaTable Returns the metatable object for the containing data control. (Defined by DynamicDataExtensions.)
Top
  Name Description
Explicit interface implemetation Private method IAttributeAccessor.GetAttribute Infrastructure. Gets an attribute of the Web control with the specified name. (Inherited from WebControl.)
Explicit interface implemetation Private method IAttributeAccessor.SetAttribute Sets an attribute of the Web control to the specified name and value. (Inherited from WebControl.)
Explicit interface implemetation Private property IControlBuilderAccessor.ControlBuilder For a description of this member, see IControlBuilderAccessor.ControlBuilder. (Inherited from Control.)
Explicit interface implemetation Private method IControlDesignerAccessor.GetDesignModeState For a description of this member, see IControlDesignerAccessor.GetDesignModeState. (Inherited from Control.)
Explicit interface implemetation Private method IControlDesignerAccessor.SetDesignModeState For a description of this member, see IControlDesignerAccessor.SetDesignModeState. (Inherited from Control.)
Explicit interface implemetation Private method IControlDesignerAccessor.SetOwnerControl Infrastructure. For a description of this member, see IControlDesignerAccessor.SetOwnerControl. (Inherited from Control.)
Explicit interface implemetation Private property IControlDesignerAccessor.UserData For a description of this member, see IControlDesignerAccessor.UserData. (Inherited from Control.)
Explicit interface implemetation Private property IDataBindingsAccessor.DataBindings For a description of this member, see IDataBindingsAccessor.DataBindings. (Inherited from Control.)
Explicit interface implemetation Private property IDataBindingsAccessor.HasDataBindings For a description of this member, see IDataBindingsAccessor.HasDataBindings. (Inherited from Control.)
Explicit interface implemetation Private property IExpressionsAccessor.Expressions For a description of this member, see IExpressionsAccessor.Expressions. (Inherited from Control.)
Explicit interface implemetation Private property IExpressionsAccessor.HasExpressions For a description of this member, see IExpressionsAccessor.HasExpressions. (Inherited from Control.)
Explicit interface implemetation Private method IParserAccessor.AddParsedSubObject For a description of this member, see IParserAccessor.AddParsedSubObject. (Inherited from Control.)
Top

In this topic:

Introduction

The FileUpload class displays a text box control and a browse button that enable users to select a file on the client and upload it to the Web server. The user specifies the file to upload by entering the full path of the file on the local computer (for example, C:\MyFiles\TestFile.txt) in the text box of the control. Alternately, the user can select the file by clicking the Browse button, and then locating it in the Choose File dialog box.

Use the FileName property to get the name of a file on a client to upload by using the FileUpload control. The file name that this property returns does not include the path of the file on the client.

The FileContent property gets a Stream object that points to a file to upload. Use this property to access the contents of the file as bytes. For example, you can use the Stream object that is returned by the FileContent property to read the contents of the file as bytes and store them in a byte array. Alternatively, you can use the FileBytes property to retrieve all the bytes in the file.

The PostedFile property gets the underlying HttpPostedFile object for the file to upload. You can use this property to access additional properties on the file. The ContentLength property gets the length of the file. The ContentType property gets the MIME content type of the file. In addition, you can use the PostedFile property to access the FileName property, the InputStream property, and the SaveAs method. However, the same functionality is provided by the FileName property, the FileContent property, and the SaveAs method.

Saving Uploaded Files

The FileUpload control does not automatically save a file to the server after the user selects the file to upload. You must explicitly provide a control or mechanism to allow the user to submit the specified file. For example, you can provide a button that the user clicks to upload the file. The code that you write to save the specified file should call the SaveAs method, which saves the contents of a file to a specified path on the server. Typically, the SaveAs method is called in an event-handling method for an event that raises a post back to the server. For example, if you provide a button to submit a file, you could include the code to save the file inside the event-handling method for the click event.

Before calling the SaveAs method to save the file to the server, use the HasFile property to verify that the FileUpload control contains a file. If the HasFile returns true, call the SaveAs method. If it returns false, display a message to the user indicating that the control does not contain a file. Do not check the PostedFile property to determine whether a file to upload exists because, by default, this property contains 0 bytes. As a result, even when the FileUpload control is blank, the PostedFile property returns a non-null value.

Security Considerations

When you call the SaveAs method, you must specify the full path of the directory in which to save the uploaded file. If you do not explicitly specify a path in your application code, an exception is thrown when a user attempts to upload a file. This behavior helps keep the files on the server secure by preventing users from being able to write to arbitrary locations in your application's directory structure, as well as preventing access to sensitive root directories.

The SaveAs method writes the uploaded file to the specified directory. Therefore, the ASP.NET application must have write access to the directory on the server. There are two ways that the application can get write access. You can explicitly grant write access to the account under which the application is running, in the directory in which the uploaded files will be saved. Alternatively, you can increase the level of trust that is granted to the ASP.NET application. To get write access to the executing directory for the application, the application must be granted the AspNetHostingPermission object with the trust level set to the AspNetHostingPermissionLevel.Medium value. Increasing the level of trust increases the application's access to resources on the server. Note that this is not a secure approach, because a malicious user who gains control of your application will also be able to run under this higher level of trust. It is a best practice to run an ASP.NET application in the context of a user with the minimum privileges that are required for the application to run. For more information about security in ASP.NET applications, see Basic Security Practices for Web Applications and ASP.NET Trust Levels and Policy Files.

Memory Limitations

One way to guard against denial of service attacks is to limit the size of the files that can be uploaded by using the FileUpload control. You should set a size limit that is appropriate for the types of files that you expect to be uploaded. The default size limit is 4096 kilobytes (KB), or 4 megabytes (MB). You can allow larger files to be uploaded by setting the maxRequestLength attribute of the httpRuntime element. To increase the maximum allowable file size for the entire application, set the maxRequestLength attribute in the Web.config file. To increase the maximum allowable file size for a specified page, set the maxRequestLength attribute inside the location element in Web.config. For an example, see location Element (ASP.NET Settings Schema).

When uploading large files, a user might also receive the following error message:

aspnet_wp.exe (PID: 1520) was recycled because memory consumption exceeded 460 MB (60 percent of available RAM).

If your users encounter this error message, increase the value of the memoryLimit attribute in the processModel of element the Web.config file for the application. The memoryLimit attribute specifies the maximum amount of memory that a worker process can use. If the worker process exceeds the memoryLimit amount, a new process is created to replace it, and all current requests are reassigned to the new process.

To control whether the file to upload is temporarily stored in memory or on the server while the request is being processed, set the requestLengthDiskThreshold attribute of the httpRuntime element. This attribute enables you to manage the size of the input stream buffer. The default is 256 bytes. The value that you specify should not exceed the value that you specify for the maxRequestLength attribute.

Using the FileUpload Control with the UpdatePanel Control

The FileUpload control is designed to be used only in postback scenarios and not in asynchronous postback scenarios during partial-page rendering. When you use a FileUpload control inside an UpdatePanel control, the file must be uploaded by using a control that is a PostBackTrigger object for the panel. UpdatePanel controls are used to update selected regions of a page instead of updating the whole page with a postback. For more information, see UpdatePanel Control Overview and Partial-Page Rendering Overview.

Declarative Syntax

Copy 
<asp:FileUpload
    AccessKey="string"
    BackColor="color name|#dddddd"
    BorderColor="color name|#dddddd"
    BorderStyle="NotSet|None|Dotted|Dashed|Solid|Double|Groove|Ridge|
        Inset|Outset"
    BorderWidth="size"
    CssClass="string"
    Enabled="True|False"
    EnableTheming="True|False"
    EnableViewState="True|False"
    Font-Bold="True|False"
    Font-Italic="True|False"
    Font-Names="string"
    Font-Overline="True|False"
    Font-Size="string|Smaller|Larger|XX-Small|X-Small|Small|Medium|
        Large|X-Large|XX-Large"
    Font-Strikeout="True|False"
    Font-Underline="True|False"
    ForeColor="color name|#dddddd"
    Height="size"
    ID="string"
    OnDataBinding="DataBinding event handler"
    OnDisposed="Disposed event handler"
    OnInit="Init event handler"
    OnLoad="Load event handler"
    OnPreRender="PreRender event handler"
    OnUnload="Unload event handler"
    runat="server"
    SkinID="string"
    Style="string"
    TabIndex="integer"
    ToolTip="string"
    Visible="True|False"
    Width="size"
/>

A Visual Studio Web site project with source code is available to accompany this topic: Download.

This section contains the following four examples:

  • The first example demonstrates how to create a FileUpload control that saves files to a path that is specified in code.

  • The second example demonstrates how to create a FileUpload control that saves files to a specified directory in the file system for the application.

  • The third example demonstrates how to create a FileUpload control that saves files to a specified path and limits the size of the file that can be uploaded.

  • The fourth example demonstrates how to create a FileUpload control that saves files to a specified path and allows only files that have the .doc or .xls file name extensions to be uploaded.

Caution note Caution

These examples demonstrate the basic syntax for the FileUpload control, but they do not demonstrate all the necessary error checking that should be completed before to saving the file. For a more complete example, see SaveAs.

The following example demonstrates how to create a FileUpload control that saves files to a path that is specified in code. The SaveAs method is called to save the file to the specified path on the server.

C#
VB
Copy 

<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 

<script runat="server">

  protected void UploadButton_Click(object sender, EventArgs e)
  {
    // Specify the path on the server to
    // save the uploaded file to.
    String savePath = @"c:\temp\uploads\";

    // Before attempting to perform operations
    // on the file, verify that the FileUpload 
    // control contains a file.
    if (FileUpload1.HasFile)
    {
      // Get the name of the file to upload.
      String fileName = FileUpload1.FileName;

      // Append the name of the file to upload to the path.
      savePath += fileName;


      // Call the SaveAs method to save the 
      // uploaded file to the specified path.
      // This example does not perform all
      // the necessary error checking.               
      // If a file with the same name
      // already exists in the specified path,  
      // the uploaded file overwrites it.
      FileUpload1.SaveAs(savePath);

      // Notify the user of the name of the file
      // was saved under.
      UploadStatusLabel.Text = "Your file was saved as " + fileName;
    }
    else
    {      
      // Notify the user that a file was not uploaded.
      UploadStatusLabel.Text = "You did not specify a file to upload.";
    }

  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>FileUpload Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
       <h4>Select a file to upload:</h4>

       <asp:FileUpload id="FileUpload1"                 
           runat="server">
       </asp:FileUpload>

       <br /><br />

       <asp:Button id="UploadButton" 
           Text="Upload file"
           OnClick="UploadButton_Click"
           runat="server">
       </asp:Button>    

       <hr />

       <asp:Label id="UploadStatusLabel"
           runat="server">
       </asp:Label>        
    </div>
    </form>
</body>
</html>

The following example demonstrates how to create a FileUpload control that saves files to a specified directory in the file system for the application. The HttpRequest.PhysicalApplicationPath property is used to get the physical file system path of the root directory for the currently executing server application. The SaveAs method is called to save the file to the specified path on the server.

C#
VB
Copy 

<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    protected void UploadButton_Click(object sender, EventArgs e)
    {
        // Save the uploaded file to an "Uploads" directory
        // that already exists in the file system of the 
        // currently executing ASP.NET application.  
        // Creating an "Uploads" directory isolates uploaded 
        // files in a separate directory. This helps prevent
        // users from overwriting existing application files by
        // uploading files with names like "Web.config".
        string saveDir = @"\Uploads\";

        // Get the physical file system path for the currently
        // executing application.
        string appPath = Request.PhysicalApplicationPath;

        // Before attempting to save the file, verify
        // that the FileUpload control contains a file.
        if (FileUpload1.HasFile)
        {
            string savePath = appPath + saveDir +
                Server.HtmlEncode(FileUpload1.FileName);

            // Call the SaveAs method to save the 
            // uploaded file to the specified path.
            // This example does not perform all
            // the necessary error checking.               
            // If a file with the same name
            // already exists in the specified path,  
            // the uploaded file overwrites it.
            FileUpload1.SaveAs(savePath);

            // Notify the user that the file was uploaded successfully.
            UploadStatusLabel.Text = "Your file was uploaded successfully.";

        }
        else
        {
            // Notify the user that a file was not uploaded.
            UploadStatusLabel.Text = "You did not specify a file to upload.";   
        }
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>FileUpload Class Example</title>
</head>
<body>
    <h3>FileUpload Class Example: Save To Application Directory</h3>
    <form id="form1" runat="server">
    <div>
       <h4>Select a file to upload:</h4>

       <asp:FileUpload id="FileUpload1"                 
           runat="server">
       </asp:FileUpload>

       <br/><br/>

       <asp:Button id="UploadButton" 
           Text="Upload file"
           OnClick="UploadButton_Click"
           runat="server">
       </asp:Button>    

       <hr />

       <asp:Label id="UploadStatusLabel"
           runat="server">
       </asp:Label>           
    </div>
    </form>
</body>
</html>

The following example demonstrates how to create a FileUpload control that saves files to a path that is specified in the code. The control limits the size of the file that can be uploaded to 5 MB. The PostedFile property is used to access the underlying ContentLength property and return the size of the file. If the size of the file to upload is less than 2 MB, the SaveAs method is called to save the file to the specified path on the server. In addition to checking for the maximum file size setting in your application code, you can set the maxRequestLength attribute of the httpRuntime element to a maximum allowable size in the configuration file for your application.

C#
VB
Copy 

<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    protected void UploadButton_Click(object sender, EventArgs e)
    {
        // Specify the path on the server to
        // save the uploaded file to.
        string savePath = @"c:\temp\uploads\";

        // Before attempting to save the file, verify
        // that the FileUpload control contains a file.
        if (FileUpload1.HasFile)
        {                
            // Get the size in bytes of the file to upload.
            int fileSize = FileUpload1.PostedFile.ContentLength;

            // Allow only files less than 2,100,000 bytes (approximately 2 MB) to be uploaded.
            if (fileSize < 2100000)
            {

                // Append the name of the uploaded file to the path.
                savePath += Server.HtmlEncode(FileUpload1.FileName);

                // Call the SaveAs method to save the 
                // uploaded file to the specified path.
                // This example does not perform all
                // the necessary error checking.               
                // If a file with the same name
                // already exists in the specified path,  
                // the uploaded file overwrites it.
                FileUpload1.SaveAs(savePath);

                // Notify the user that the file was uploaded successfully.
                UploadStatusLabel.Text = "Your file was uploaded successfully.";
            }
            else
            {
                // Notify the user why their file was not uploaded.
                UploadStatusLabel.Text = "Your file was not uploaded because " + 
                                         "it exceeds the 2 MB size limit.";
            }
        }   
        else
        {
            // Notify the user that a file was not uploaded.
            UploadStatusLabel.Text = "You did not specify a file to upload.";
        }
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>FileUpload Class Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
       <h4>Select a file to upload:</h4>

       <asp:FileUpload id="FileUpload1"                 
           runat="server">
       </asp:FileUpload>

       <br/><br/>

       <asp:Button id="UploadButton" 
           Text="Upload file"
           OnClick="UploadButton_Click"
           runat="server">
       </asp:Button>

       <hr />

       <asp:Label id="UploadStatusLabel"
           runat="server">
       </asp:Label>

    </div>
    </form>
</body>
</html>

The following example demonstrates how to create a FileUpload control that saves files to a path that is specified in the code. This example allows only files that have the .doc or .xls file name extensions to be uploaded. The Path.GetExtension method is called to return the extension of the file to upload. If the file has a .doc or .xls file name extension, the SaveAs method is called to save the file to the specified path on the server.

C#
VB
Copy 

<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    protected void UploadBtn_Click(object sender, EventArgs e)
    {
        // Specify the path on the server to
        // save the uploaded file to.
        string savePath = @"c:\temp\uploads";

        // Before attempting to save the file, verify
        // that the FileUpload control contains a file.
        if (FileUpload1.HasFile)
        {
            // Get the name of the file to upload.
            string fileName = Server.HtmlEncode(FileUpload1.FileName);

            // Get the extension of the uploaded file.
            string extension = System.IO.Path.GetExtension(fileName);

            // Allow only files with .doc or .xls extensions
            // to be uploaded.
            if ((extension == ".doc") || (extension == ".xls"))
            {
                // Append the name of the file to upload to the path.
                savePath += fileName;

                // Call the SaveAs method to save the 
                // uploaded file to the specified path.
                // This example does not perform all
                // the necessary error checking.               
                // If a file with the same name
                // already exists in the specified path,  
                // the uploaded file overwrites it.
                FileUpload1.SaveAs(savePath);

                // Notify the user that their file was successfully uploaded.
                UploadStatusLabel.Text = "Your file was uploaded successfully.";
            }
            else
            {
                // Notify the user why their file was not uploaded.
                UploadStatusLabel.Text = "Your file was not uploaded because " + 
                                         "it does not have a .doc or .xls extension.";
            }

        }

    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>FileUpload Class Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h4>Select a file to upload:</h4>

        <asp:FileUpload id="FileUpload1"                 
            runat="server">
        </asp:FileUpload>

        <br/><br/>

        <asp:Button id="UploadBtn" 
            Text="Upload file"
            OnClick="UploadBtn_Click"
            runat="server">
        </asp:Button>    

        <hr />

        <asp:Label id="UploadStatusLabel"
            runat="server">
        </asp:Label>     
    </div>
    </form>
</body>
</html>

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Did you find this helpful?
(1500 characters remaining)
Community Content Add
Annotations FAQ
Only File name in GoogleBrowser
I m using fileupload control to get the upload file name and path. I get the complete file path when using IE 6. were as when I run the same program in Google it provides only the filename instead of full path. I noticed there is no method, property providing the complete path when running the program via CromeBrowser Version 17. Any solution ?
History
Why the asynchronous upload is not yet supported I wonder
The technology is moving ahead but I see no improvement in file upload,its the same old html post scenario, Fileupload still not compatible with updatepanel, we would have a fix for that by now, anyway its for security and html limitations perhaps, with the introduction of HTML 5 I would expect more improvement on FileUpload Technology of Asp.net.

As for asynchronous fileupload we have support via Ajax control toolkit.
http://www.asp.net/ajaxLibrary/AjaxControlToolkitSampleSite/AsyncFileUpload/AsyncFileUpload.aspx

And there are more open source controls and article that did solved the problem in a good way. Hope those will be incorporated in Fileupload in near future.


History
Awesome
Really it is a very helpful for the web development I really like this information it is too informative and helpful...  <a href="http://marshallindex.com/">latest news today</a>
History
Tips & Tricks
Nice!
History
Checking file size prior to upload
Some notes about checking file size and handling it with appropriate message if it exceeds a certain size would be a valuable addition to this article.
History
How To Change BackColor Of "Browse" Button Of FileUpload Control
The ASPX FileUpload control displays a TextBox along with a 'Browse...'
Button. Setting the different properties of this control just reflects
the changes in the TextBox but not the Button.

For e.g. if the BackColor of a FileUpload control is set to blue, then
only the TextBox color changes to blue but the BackColor of the Button
doesn't change to blue. Or if the Font-Size of a FileUpload control is
set to 15pt, then only the size of the text in the TextBox becomes 15pt
but the 'Browse...' text on the Button retains the default size.

Is there any way by which the properties of the Button (like BackColor,
BorderColor, Font-Names etc.) in the FileUpload control can also be
changed along with the TextBox?

Thanx in Advance
Mayur Panchal.....
History
Different behaviour for FileName Property
Note that FileName has a different behaviour depending on the windows version in combination with the browser version.

While using IE6 on Windows 7 or using IE7 on Windows XP the FileName property is filled with the ENTIRE path including the file.

While using IE7/IE8/FireFox on Windows 7 is filled as expected from the content with just the filename.
History
Re: Mark Minasi on UAC and R2 Win7 interview at TechEd09

http://www.airmax-shox.com/en/category/7-air-max-90.html

Nice post,nice sharing.Thanks!

History
Re: Windows Vista SP1 UAC improvements

Thanks for sharing cheap cialis online

History
Re: IE 8 RTM and Top 5 reasons for IT Pros to deploy

I first used it because of the easiness to deploy, but there are apprently more great features you can find later. Minneapolis web design

History