BoundField Class

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

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

public ref class BoundField : System::Web::UI::WebControls::DataControlField

public class BoundField : System.Web.UI.WebControls.DataControlField

type BoundField = class
    inherit DataControlField

Public Class BoundField
Inherits DataControlField

Inheritance: Object

DataControlField
BoundField

Derived: System.Web.UI.WebControls.AutoGeneratedField

System.Web.UI.WebControls.CheckBoxField

Examples

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


<%@ 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>


<%@ Page language="VB" %>

<!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>

Remarks

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

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.

Constructors

BoundField()

Initializes a new instance of the BoundField class.

Fields

ThisExpression

This API supports the product infrastructure and is not intended to be used directly from your code.

Represents the "this" expression.

Properties

AccessibleHeaderText	Gets or sets text that is rendered as the `AbbreviatedText` property value in some controls. (Inherited from DataControlField)
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.
Control	Gets a reference to the data control that the DataControlField object is associated with. (Inherited from DataControlField)
ControlStyle	Gets the style of any Web server controls contained by the DataControlField object. (Inherited from DataControlField)
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.
DataField	Gets or sets the name of the data field to bind to the BoundField object.
DataFormatString	Gets or sets the string that specifies the display format for the value of the field.
DesignMode	Gets a value indicating whether a data control field is currently viewed in a design-time environment. (Inherited from DataControlField)
FooterStyle	Gets or sets the style of the footer of the data control field. (Inherited from DataControlField)
FooterText	Gets or sets the text that is displayed in the footer item of a data control field. (Inherited from DataControlField)
HeaderImageUrl	Gets or sets the URL of an image that is displayed in the header item of a data control field. (Inherited from DataControlField)
HeaderStyle	Gets or sets the style of the header of the data control field. (Inherited from DataControlField)
HeaderText	Gets or sets the text that is displayed in the header of a data control.
HtmlEncode	Gets or sets a value indicating whether field values are HTML-encoded before they are displayed in a BoundField object.
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.
InsertVisible	Gets a value indicating whether the DataControlField object is visible when its parent data-bound control is in insert mode. (Inherited from DataControlField)
IsTrackingViewState	Gets a value indicating whether the DataControlField object is saving changes to its view state. (Inherited from DataControlField)
ItemStyle	Gets the style of any text-based content displayed by a data control field. (Inherited from DataControlField)
NullDisplayText	Gets or sets the caption displayed for a field when the field's value is null.
ReadOnly	Gets or sets a value indicating whether the value of the field can be modified in edit mode.
ShowHeader	Gets or sets a value indicating whether the header item of a data control field is rendered. (Inherited from DataControlField)
SortExpression	Gets or sets a sort expression that is used by a data source control to sort data. (Inherited from DataControlField)
SupportsHtmlEncode	Gets a value indicating whether HTML encoding is supported by a BoundField object.
ValidateRequestMode	Gets or sets a value that determines whether the control validates client input or not.
ValidateRequestMode	Gets or sets a value that specifies whether the control validates client input. (Inherited from DataControlField)
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)
Visible	Gets or sets a value indicating whether a data control field is rendered. (Inherited from DataControlField)

Methods

CloneField()	Creates a duplicate copy of the current DataControlField-derived object. (Inherited from DataControlField)
CopyProperties(DataControlField)	Copies the properties of the current BoundField object to the specified DataControlField object.
CreateField()	Creates an empty BoundField object.
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
ExtractValuesFromCell(IOrderedDictionary, DataControlFieldCell, DataControlRowState, Boolean)	Fills the specified IDictionary object with the values from the specified TableCell object.
FormatDataValue(Object, Boolean)	Formats the specified field value for a cell in the BoundField object.
GetDesignTimeValue()	Retrieves the value used for a field's value when rendering the BoundField object in a designer.
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetType()	Gets the Type of the current instance. (Inherited from Object)
GetValue(Control)	Retrieves the value of the field bound to the BoundField object.
Initialize(Boolean, Control)	Initializes the BoundField object.
InitializeCell(DataControlFieldCell, DataControlCellType, DataControlRowState, Int32)	Initializes the specified TableCell object to the specified row state.
InitializeDataCell(DataControlFieldCell, DataControlRowState)	Initializes the specified TableCell object to the specified row state.
LoadViewState(Object)	Restores the previously stored view-state information for this field.
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
OnDataBindField(Object, EventArgs)	Binds the value of a field to the BoundField object.
OnFieldChanged()	Raises the `FieldChanged` event. (Inherited from DataControlField)
SaveViewState()	Saves the changes made to the DataControlField view state since the time the page was posted back to the server. (Inherited from DataControlField)
ToString()	Returns a string that represents this DataControlField object. (Inherited from DataControlField)
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)
ValidateSupportsCallback()	Determines whether the controls contained in a BoundField object support callbacks.

Explicit Interface Implementations

IDataSourceViewSchemaAccessor.DataSourceViewSchema	Gets or sets the schema associated with this DataControlField object. (Inherited from DataControlField)
IStateManager.IsTrackingViewState	Gets a value indicating whether the DataControlField object is saving changes to its view state. (Inherited from DataControlField)
IStateManager.LoadViewState(Object)	Restores the data control field's previously saved view state. (Inherited from DataControlField)
IStateManager.SaveViewState()	Saves the changes made to the DataControlField view state since the time the page was posted back to the server. (Inherited from DataControlField)
IStateManager.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)

Applies to

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