HttpFileCollection Class

Definition

Provides access to and organizes files uploaded by a client.

public ref class HttpFileCollection sealed : System::Collections::Specialized::NameObjectCollectionBase
public sealed class HttpFileCollection : System.Collections.Specialized.NameObjectCollectionBase
type HttpFileCollection = class
    inherit NameObjectCollectionBase
Public NotInheritable Class HttpFileCollection
Inherits NameObjectCollectionBase
Inheritance
HttpFileCollection

Examples

The following example demonstrates how to access the HttpFileCollection collection returned from the Files property of the HttpRequest object. The HttpFileCollection collection is populated by two FileUpload controls on the Web page. Items in the file collection are displayed in a BulletedList control.

<%@ 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 Button1_Click(object sender, EventArgs e)
    {
        // Clear the BulletedList.
        BulletedList1.Items.Clear();
        
        // Check to see if at least one file was specified.
        if (FileUpload1.HasFile | FileUpload2.HasFile)
        {
            Label1.Text = "The file collection consists of:";
            
            // Get the HttpFileCollection.
            HttpFileCollection hfc = Request.Files;
            foreach (String h in hfc.AllKeys)
            {
                // Add an item to the BulletedList if a file
                // was specified for the corresponding control.
                if (hfc[h].ContentLength > 0)
                    BulletedList1.Items.Add(Server.HtmlEncode(hfc[h].FileName));
            }
            
        }
        else
        {
            Label1.Text = "You did not specify any files to upload or " +
                "the file(s) could not be found.";
        }

    }        
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>HttpFileCollection Example</title>
</head>
<body>
    <form id="form1" 
          runat="server">
    <div>
        <asp:FileUpload ID="FileUpload1" 
                        runat="server" />
        <br />
        <asp:FileUpload ID="FileUpload2" 
                        runat="server" />
        <br />
        <asp:Button ID="Button1" 
                    runat="server" 
                    OnClick="Button1_Click" 
                    Text="Upload" />
        <br />
        <asp:Label ID="Label1" 
                   runat="server"/>
        <br />
        <asp:BulletedList ID="BulletedList1" 
                          runat="server">
        </asp:BulletedList>
        </div>
    </form>
</body>
</html>
<%@ Page Language="VB" %>

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

<script runat="server">

    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)

        ' Clear the BulletedList.
        BulletedList1.Items.Clear()
        
        ' Check to see if at least one file was specified.
        If (FileUpload1.HasFile Or FileUpload2.HasFile) Then
            
            Label1.Text = "The file collection consists of:"
            
            ' Get the HttpFileCollection.
            Dim hfc As HttpFileCollection = Request.Files
            For Each h As String In hfc.AllKeys
                
                ' Add an item to the BulletedList if a file
                ' was specified for the corresponding control.
                If (hfc(h).ContentLength > 0) Then
                    BulletedList1.Items.Add(Server.HtmlEncode(hfc(h).FileName))
                End If
            Next
        Else
            
            Label1.Text = "You did not specify any files to upload or " & _
                "the file(s) could not be found."
            
        End If
    End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>HttpFileCollection Example</title>
</head>
<body>
    <form id="form1" 
          runat="server">
    <div>
        <asp:FileUpload ID="FileUpload1" 
                        runat="server" />
        <br />
        <asp:FileUpload ID="FileUpload2" 
                        runat="server" />
        <br />
        <asp:Button ID="Button1" 
                    runat="server" 
                    OnClick="Button1_Click" 
                    Text="Upload" />
        <br />
        <asp:Label ID="Label1" 
                   runat="server"/>
        <br />
        <asp:BulletedList ID="BulletedList1" 
                          runat="server">
        </asp:BulletedList>
        </div>
    </form>
</body>
</html>

Remarks

Clients encode files and transmit them in the content body using multipart MIME format with an HTTP Content-Type header of multipart/form-data. ASP.NET extracts the encoded file(s) from the content body into individual members of an HttpFileCollection. Methods and properties of the HttpPostedFile class provide access to the contents and properties of each file.

Properties

AllKeys

Gets a string array containing the keys (names) of all members in the file collection.

Count

Gets the number of key/value pairs contained in the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
IsReadOnly

Gets or sets a value indicating whether the NameObjectCollectionBase instance is read-only.

(Inherited from NameObjectCollectionBase)
Item[Int32]

Gets the object with the specified numerical index from the HttpFileCollection.

Item[String]

Gets the object with the specified name from the file collection.

Keys

Gets a NameObjectCollectionBase.KeysCollection instance that contains all the keys in the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)

Methods

BaseAdd(String, Object)

Adds an entry with the specified key and value into the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseClear()

Removes all entries from the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseGet(Int32)

Gets the value of the entry at the specified index of the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseGet(String)

Gets the value of the first entry with the specified key from the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseGetAllKeys()

Returns a String array that contains all the keys in the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseGetAllValues()

Returns an Object array that contains all the values in the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseGetAllValues(Type)

Returns an array of the specified type that contains all the values in the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseGetKey(Int32)

Gets the key of the entry at the specified index of the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseHasKeys()

Gets a value indicating whether the NameObjectCollectionBase instance contains entries whose keys are not null.

(Inherited from NameObjectCollectionBase)
BaseRemove(String)

Removes the entries with the specified key from the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseRemoveAt(Int32)

Removes the entry at the specified index of the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseSet(Int32, Object)

Sets the value of the entry at the specified index of the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
BaseSet(String, Object)

Sets the value of the first entry with the specified key in the NameObjectCollectionBase instance, if found; otherwise, adds an entry with the specified key and value into the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
CopyTo(Array, Int32)

Copies members of the file collection to an Array beginning at the specified index of the array.

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
Get(Int32)

Returns the HttpPostedFile object with the specified numerical index from the file collection.

Get(String)

Returns the HttpPostedFile object with the specified name from the file collection.

GetEnumerator()

Returns an enumerator that iterates through the NameObjectCollectionBase.

(Inherited from NameObjectCollectionBase)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetKey(Int32)

Returns the name of the HttpFileCollection member with the specified numerical index.

GetMultiple(String)

Returns all files that match the specified name.

GetObjectData(SerializationInfo, StreamingContext)
Obsolete.

Implements the ISerializable interface and returns the data needed to serialize the NameObjectCollectionBase instance.

(Inherited from NameObjectCollectionBase)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
OnDeserialization(Object)

Implements the ISerializable interface and raises the deserialization event when the deserialization is complete.

(Inherited from NameObjectCollectionBase)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Explicit Interface Implementations

ICollection.CopyTo(Array, Int32)

Copies the entire NameObjectCollectionBase to a compatible one-dimensional Array, starting at the specified index of the target array.

(Inherited from NameObjectCollectionBase)
ICollection.IsSynchronized

Gets a value indicating whether access to the NameObjectCollectionBase object is synchronized (thread safe).

(Inherited from NameObjectCollectionBase)
ICollection.SyncRoot

Gets an object that can be used to synchronize access to the NameObjectCollectionBase object.

(Inherited from NameObjectCollectionBase)

Extension Methods

Cast<TResult>(IEnumerable)

Casts the elements of an IEnumerable to the specified type.

OfType<TResult>(IEnumerable)

Filters the elements of an IEnumerable based on a specified type.

AsParallel(IEnumerable)

Enables parallelization of a query.

AsQueryable(IEnumerable)

Converts an IEnumerable to an IQueryable.

Applies to

See also