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BoundField Class

.NET Framework 4

Represents a field that is displayed as text in a data-bound control.

System.Object
  System.Web.UI.WebControls.DataControlField
    System.Web.UI.WebControls.BoundField
      System.Web.UI.WebControls.AutoGeneratedField
      System.Web.UI.WebControls.CheckBoxField

Namespace:  System.Web.UI.WebControls
Assembly:  System.Web (in System.Web.dll)
C#
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public class BoundField : DataControlField

The BoundField type exposes the following members.

  Name Description
Public method BoundField Initializes a new instance of the BoundField class.
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  Name Description
Public property AccessibleHeaderText Gets or sets text that is rendered as the AbbreviatedText property value in some controls. (Inherited from DataControlField.)
Public property ApplyFormatInEditMode Gets or sets a value indicating whether the formatting string specified by the DataFormatString property is applied to field values when the data-bound control that contains the BoundField object is in edit mode.
Protected property Control Gets a reference to the data control that the DataControlField object is associated with. (Inherited from DataControlField.)
Public property ControlStyle Gets the style of any Web server controls contained by the DataControlField object. (Inherited from DataControlField.)
Public property ConvertEmptyStringToNull Gets or sets a value indicating whether empty string values ("") are automatically converted to null values when the data field is updated in the data source.
Public property DataField Gets or sets the name of the data field to bind to the BoundField object.
Public property DataFormatString Gets or sets the string that specifies the display format for the value of the field.
Protected property DesignMode Gets a value indicating whether a data control field is currently viewed in a design-time environment. (Inherited from DataControlField.)
Public property FooterStyle Gets or sets the style of the footer of the data control field. (Inherited from DataControlField.)
Public property FooterText Gets or sets the text that is displayed in the footer item of a data control field. (Inherited from DataControlField.)
Public property HeaderImageUrl Gets or sets the URL of an image that is displayed in the header item of a data control field. (Inherited from DataControlField.)
Public property HeaderStyle Gets or sets the style of the header of the data control field. (Inherited from DataControlField.)
Public property HeaderText Gets or sets the text that is displayed in the header of a data control. (Overrides DataControlField.HeaderText.)
Public property HtmlEncode Gets or sets a value indicating whether field values are HTML-encoded before they are displayed in a BoundField object.
Public property HtmlEncodeFormatString Gets or sets a value that indicates whether text that is created by applying the DataFormatString property to the BoundField value should be HTML encoded when it is displayed.
Public property InsertVisible Gets a value indicating whether the DataControlField object is visible when its parent data-bound control is in insert mode. (Inherited from DataControlField.)
Protected property IsTrackingViewState Gets a value indicating whether the DataControlField object is saving changes to its view state. (Inherited from DataControlField.)
Public property ItemStyle Gets the style of any text-based content displayed by a data control field. (Inherited from DataControlField.)
Public property NullDisplayText Gets or sets the caption displayed for a field when the field's value is null.
Public property ReadOnly Gets or sets a value indicating whether the value of the field can be modified in edit mode.
Public property ShowHeader Gets or sets a value indicating whether the header item of a data control field is rendered. (Inherited from DataControlField.)
Public property SortExpression Gets or sets a sort expression that is used by a data source control to sort data. (Inherited from DataControlField.)
Protected property SupportsHtmlEncode Gets a value indicating whether HTML encoding is supported by a BoundField object.
Protected property ViewState Gets a dictionary of state information that allows you to save and restore the view state of a DataControlField object across multiple requests for the same page. (Inherited from DataControlField.)
Public property Visible Gets or sets a value indicating whether a data control field is rendered. (Inherited from DataControlField.)
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  Name Description
Protected method CloneField Infrastructure. Creates a duplicate copy of the current DataControlField-derived object. (Inherited from DataControlField.)
Protected method CopyProperties Copies the properties of the current BoundField object to the specified DataControlField object. (Overrides DataControlField.CopyProperties(DataControlField).)
Protected method CreateField Creates an empty BoundField object. (Overrides DataControlField.CreateField().)
Public method Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Public method ExtractValuesFromCell Fills the specified System.Collections.IDictionary object with the values from the specified TableCell object. (Overrides DataControlField.ExtractValuesFromCell(IOrderedDictionary, DataControlFieldCell, DataControlRowState, Boolean).)
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.)
Protected method FormatDataValue Formats the specified field value for a cell in the BoundField object.
Protected method GetDesignTimeValue Retrieves the value used for a field's value when rendering the BoundField object in a designer.
Public method GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Protected method GetValue Retrieves the value of the field bound to the BoundField object.
Public method Initialize Initializes the BoundField object. (Overrides DataControlField.Initialize(Boolean, Control).)
Public method InitializeCell Initializes the specified TableCell object to the specified row state. (Overrides DataControlField.InitializeCell(DataControlFieldCell, DataControlCellType, DataControlRowState, Int32).)
Protected method InitializeDataCell Initializes the specified TableCell object to the specified row state.
Protected method LoadViewState Restores the previously stored view-state information for this field. (Overrides DataControlField.LoadViewState(Object).)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Protected method OnDataBindField Binds the value of a field to the BoundField object.
Protected method OnFieldChanged Raises the FieldChanged event. (Inherited from DataControlField.)
Protected method SaveViewState Saves the changes made to the DataControlField view state since the time the page was posted back to the server. (Inherited from DataControlField.)
Public method ToString Returns a string that represents this DataControlField object. (Inherited from DataControlField.)
Protected method TrackViewState Causes the DataControlField object to track changes to its view state so they can be stored in the control's ViewState property and persisted across requests for the same page. (Inherited from DataControlField.)
Public method ValidateSupportsCallback Determines whether the controls contained in a BoundField object support callbacks. (Overrides DataControlField.ValidateSupportsCallback().)
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  Name Description
Public field Static member ThisExpression Infrastructure. Represents the "this" expression.
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  Name Description
Explicit interface implemetation Private property IDataSourceViewSchemaAccessor.DataSourceViewSchema Infrastructure. Gets or sets the schema associated with this DataControlField object. (Inherited from DataControlField.)
Explicit interface implemetation Private property IStateManager.IsTrackingViewState Infrastructure. Gets a value indicating whether the DataControlField object is saving changes to its view state. (Inherited from DataControlField.)
Explicit interface implemetation Private method IStateManager.LoadViewState Infrastructure. Restores the data control field's previously saved view state. (Inherited from DataControlField.)
Explicit interface implemetation Private method IStateManager.SaveViewState Infrastructure. Saves the changes made to the DataControlField view state since the time the page was posted back to the server. (Inherited from DataControlField.)
Explicit interface implemetation Private method IStateManager.TrackViewState Infrastructure. Causes the DataControlField object to track changes to its view state so they can be stored in the control's ViewState property and persisted across requests for the same page. (Inherited from DataControlField.)
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The BoundField class is used by data-bound controls (such as GridView and DetailsView) to display the value of a field as text. The BoundField object is displayed differently depending on the data-bound control in which it is used. For example, the GridView control displays a BoundField object as a column, while the DetailsView control displays it as a row.

To specify the field to display in a BoundField object, set the DataField property to the field's name. The field's value can be HTML-encoded before it is displayed by setting the HtmlEncode property to true. You can apply a custom formatting string to the field's value by setting the DataFormatString property. When the HtmlEncode property is true, the encoded string value of the field is used in the custom format string. By default, the formatting string is applied to field values only when the data-bound control is in read-only mode. To apply the formatting string to values displayed while the data-bound control is in edit mode, set the ApplyFormatInEditMode property to true. If a field's value is null, you can display a custom caption by setting the NullDisplayText property. The BoundField object can also automatically convert empty string ("") field values to null values by setting the ConvertEmptyStringToNull property to true.

You can hide a BoundField object in a data-bound control by setting the Visible property to false. To prevent the value of a field from being modified in edit mode, set the ReadOnly property to true. In data-bound controls that support inserting records (such as the DetailsView control), you can hide a BoundField object by setting the InsertVisible property to false. This is commonly done when you want to hide an automatically generated key field in insert mode.

You can customize the header and footer sections of a BoundField object. To display a caption in the header or footer sections, set the HeaderText or FooterText properties, respectively. Instead of displaying text in the header section, you can display an image by setting the HeaderImageUrl property. The header section can be hidden in the BoundField object by setting the ShowHeader property to false.

Note Note

Some data-bound controls (such as the GridView control) can show or hide only the entire header section of the control. These data-bound controls do not support the ShowHeader property for an individual bound field. To show or hide the entire header section of a data-bound control (if available), use the control's ShowHeader property.

You also can customize the appearance of the BoundField object (font color, background color, and so on) by setting the style properties for the different parts of the field. The following table lists the different style properties.

Style property

Description

ControlStyle

The style settings for the child Web server controls of the BoundField object.

FooterStyle

The style settings for the footer section of the BoundField object.

HeaderStyle

The style settings for the header section of the BoundField object.

ItemStyle

The style settings for the data items in the BoundField object.

The following code example demonstrates how to use a BoundField object to display the values of a field in a GridView control.

C#
VB
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<%@ Page language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>BoundField Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>BoundField Example</h3>

      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="false"
        autogenerateeditbutton="true"
        allowpaging="true" 
        datakeynames="CustomerID"  
        runat="server">

        <columns>
          <asp:boundfield datafield="CustomerID"
            readonly="true"      
            headertext="Customer ID"/>
          <asp:boundfield datafield="CompanyName"
            convertemptystringtonull="true"
            headertext="Customer Name"/>
          <asp:boundfield datafield="Address"
            convertemptystringtonull="true"
            headertext="Address"/>
          <asp:boundfield datafield="City"
            convertemptystringtonull="true"
            headertext="City"/>
          <asp:boundfield datafield="PostalCode"
            convertemptystringtonull="true"
            headertext="ZIP Code"/>
          <asp:boundfield datafield="Country"
            convertemptystringtonull="true"
            headertext="Country"/>
        </columns>

      </asp:gridview>

      <!-- This example uses Microsoft SQL Server and connects  -->
      <!-- to the Northwind sample database. Use an ASP.NET     -->
      <!-- expression to retrieve the connection string value   -->
      <!-- from the Web.config file.                            -->
      <asp:sqldatasource id="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers Set CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country Where (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>

    </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.
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