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ButtonField Class

Definition

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

public ref class ButtonField : System::Web::UI::WebControls::ButtonFieldBase
public class ButtonField : System.Web.UI.WebControls.ButtonFieldBase
type ButtonField = class
    inherit ButtonFieldBase
Public Class ButtonField
Inherits ButtonFieldBase
Inheritance

Examples

The following code example demonstrates how to use a ButtonField object to display a column of command buttons 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">
<script runat="server">

  void CustomersGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
  {
  
    // If multiple ButtonField column fields are used, use the
    // CommandName property to determine which button was clicked.
    if(e.CommandName=="Select")
    {
    
      // Convert the row index stored in the CommandArgument
      // property to an Integer.
      int index = Convert.ToInt32(e.CommandArgument);    
    
      // Get the last name of the selected author from the appropriate
      // cell in the GridView control.
      GridViewRow selectedRow = CustomersGridView.Rows[index];
      TableCell contactName = selectedRow.Cells[1];
      string contact = contactName.Text;  
    
      // Display the selected author.
      Message.Text = "You selected " + contact + ".";
      
    }
    
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ButtonField Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>ButtonField Example</h3>
      
      <asp:label id="Message"
        forecolor="Red"
        runat="server"
        AssociatedControlID="CustomersGridView"/>
                    
      <!-- Populate the Columns collection declaratively. -->
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="false"
        onrowcommand="CustomersGridView_RowCommand"
        runat="server">
                
        <columns>
                
          <asp:buttonfield buttontype="Button" 
            commandname="Select"
            headertext="Select Customer" 
            text="Select"/>
          <asp:boundfield datafield="CompanyName" 
            headertext="Company Name"/>
          <asp:boundfield datafield="ContactName" 
            headertext="Contact Name"/>
                
        </columns>
                
      </asp:gridview>
            
        <!-- This example uses Microsoft SQL Server and connects -->
        <!-- to the Northwind sample database.                   -->
        <asp:sqldatasource id="CustomersSqlDataSource"  
          selectcommand="Select [CustomerID], [CompanyName], [ContactName], [ContactTitle] From [Customers]"
          connectionstring="<%$ ConnectionStrings:NorthWindConnection%>"
          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">
<script runat="server">

    Sub CustomersGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)
  
        ' If multiple ButtonField column fields are used, use the
        ' CommandName property to determine which button was clicked.
        If e.CommandName = "Select" Then
    
            ' Convert the row index stored in the CommandArgument
            ' property to an Integer.
            Dim index As Integer = Convert.ToInt32(e.CommandArgument)
    
            ' Get the last name of the selected author from the appropriate
            ' cell in the GridView control.
            Dim selectedRow As GridViewRow = CustomersGridView.Rows(index)
            Dim contactCell As TableCell = selectedRow.Cells(1)
            Dim contact As String = contactCell.Text
    
            ' Display the selected author.
            Message.Text = "You selected " & contact & "."
      
        End If
    
    End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ButtonField Example</title>
</head>
<body>
    <form id="Form1" runat="server">
        
      <h3>ButtonField Example</h3>
      
      <asp:label id="Message"
        forecolor="Red"
        runat="server"
        AssociatedControlID="CustomersGridView"/>
                    
      <!-- Populate the Columns collection declaratively. -->
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="false"
        onrowcommand="CustomersGridView_RowCommand"
        runat="server">
                
        <columns>
                
          <asp:buttonfield buttontype="Button" 
            commandname="Select"
            headertext="Select Customer" 
            text="Select"/>
          <asp:boundfield datafield="CompanyName" 
            headertext="Company Name"/>
          <asp:boundfield datafield="ContactName" 
            headertext="Contact Name"/>
                
        </columns>
                
      </asp:gridview>
            
        <!-- This example uses Microsoft SQL Server and connects -->
        <!-- to the Northwind sample database.                   -->
        <asp:sqldatasource id="CustomersSqlDataSource"  
          selectcommand="Select [CustomerID], [CompanyName], [ContactName], [ContactTitle] From [Customers]"
          connectionstring="<%$ ConnectionStrings:NorthWindConnection%>"
          runat="server">
        </asp:sqldatasource>
            
    </form>
  </body>
</html>

Remarks

The ButtonField class is used by data-bound controls (such as GridView and DetailsView) to display a button for each record that is displayed. The ButtonField object is displayed differently depending on the data-bound control in which it is used. For example, the GridView control displays a ButtonField object as a column, while the DetailsView control displays it as a row.

Clicking a button in a button field raises the command event of the parent data-bound control. You can provide a custom routine to perform when a command button is clicked by providing an event handler for the command event.

Note

The GridView control raises the RowCommand event, while the DetailsView control raises the ItemCommand event.

To determine the index of the record that raises the command event, use the CommandArgument property of the event argument that is passed to the command event for the data-bound control. The ButtonField class automatically populates the CommandArgument property with the appropriate index value.

To specify the type of button to display, use the ButtonType property. When displaying a link or command button, use the Text property to specify the caption to display in the buttons.

Note

If you set the Text property, all buttons in a ButtonField share the same caption.

Alternatively, you can bind the ButtonField object to a field in a data source. This allows you to display different captions for the buttons in the ButtonField object. The values that are in the specified field are used for the text captions of the buttons. Set the DataTextField property to bind a ButtonField object to a field in a data source.

When displaying an image button, use the ImageUrl property to specify the image to display for the buttons in the ButtonField object.

Note

All buttons in a ButtonField object share the same image.

You can hide a ButtonField object in a data-bound control by setting the Visible property to false.

The ButtonField object allows you to customize its header and footer sections. To display a caption in the header or footer section, 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. To hide the header section in a ButtonField object, set 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 button field. To show or hide the entire header section of a data-bound control (if available), use the ShowHeader property for the control.

You also can customize the appearance of the ButtonField 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 The style settings for
ControlStyle The child Web server controls of the ButtonField.
FooterStyle The footer section of the ButtonField.
HeaderStyle The header section of the ButtonField.
ItemStyle The data items in the ButtonField.

Constructors

ButtonField()

Initializes a new instance of the ButtonField class.

Properties

AccessibleHeaderText

Gets or sets text that is rendered as the AbbreviatedText property value in some controls.

(Inherited from DataControlField)
ButtonType

Gets or sets the button type to display in the button field.

(Inherited from ButtonFieldBase)
CausesValidation

Gets or sets a value indicating whether validation is performed when a button in a ButtonFieldBase object is clicked.

(Inherited from ButtonFieldBase)
CommandName

Gets or sets a string that represents the action to perform when a button in a ButtonField object is clicked.

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)
DataTextField

Gets or sets the name of the data field for which the value is bound to the Text property of the Button control that is rendered by the ButtonField object.

DataTextFormatString

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 item of a data control field.

(Inherited from DataControlField)
ImageUrl

Gets or sets the image to display for each button in the ButtonField object.

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)
ShowHeader

Gets or sets a value indicating whether the header section is displayed in a ButtonFieldBase object.

(Inherited from ButtonFieldBase)
SortExpression

Gets or sets a sort expression that is used by a data source control to sort data.

(Inherited from DataControlField)
Text

Gets or sets the static caption that is displayed for each button in the ButtonField object.

ValidateRequestMode

Gets or sets a value that specifies whether the control validates client input.

(Inherited from DataControlField)
ValidationGroup

Gets or sets the name of the group of validation controls to validate when a button in a ButtonFieldBase object is clicked.

(Inherited from ButtonFieldBase)
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 ButtonField object to the specified DataControlField object.

CreateField()

Creates and returns a new instance of the ButtonField class.

Equals(Object)

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

(Inherited from Object)
ExtractValuesFromCell(IOrderedDictionary, DataControlFieldCell, DataControlRowState, Boolean)

Extracts the value of the data control field from the current table cell and adds the value to the specified IDictionary collection.

(Inherited from DataControlField)
FormatDataTextValue(Object)

Formats the specified field value for a cell in the ButtonField object.

GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
Initialize(Boolean, Control)

Initializes the current ButtonField object.

InitializeCell(DataControlFieldCell, DataControlCellType, DataControlRowState, Int32)

Initializes the specified DataControlFieldCell object to the specified row state.

LoadViewState(Object)

Restores the data source view's previously saved view state.

(Inherited from DataControlField)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from 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 that are contained in a ButtonField 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

See also