ClientScriptManager.GetPostBackEventReference Method

Definition

Namespace:

System.Web.UI

Assembly:

System.Web.dll

Returns a string that can be used in a client event to cause postback to the server.

Overloads

GetPostBackEventReference(Control, String, Boolean)	Returns a string to use in a client event to cause postback to the server. The reference string is defined by the specified control that handles the postback and a string argument of additional event information. Optionally, registers the event reference for validation.
GetPostBackEventReference(PostBackOptions, Boolean)	Returns a string that can be used in a client event to cause postback to the server. The reference string is defined by the specified PostBackOptions object. Optionally, registers the event reference for validation.
GetPostBackEventReference(PostBackOptions)	Returns a string that can be used in a client event to cause postback to the server. The reference string is defined by the specified PostBackOptions instance.
GetPostBackEventReference(Control, String)	Returns a string that can be used in a client event to cause postback to the server. The reference string is defined by the specified control that handles the postback and a string argument of additional event information.

GetPostBackEventReference(Control, String, Boolean)

Returns a string to use in a client event to cause postback to the server. The reference string is defined by the specified control that handles the postback and a string argument of additional event information. Optionally, registers the event reference for validation.

public:
 System::String ^ GetPostBackEventReference(System::Web::UI::Control ^ control, System::String ^ argument, bool registerForEventValidation);

public string GetPostBackEventReference (System.Web.UI.Control control, string argument, bool registerForEventValidation);

member this.GetPostBackEventReference : System.Web.UI.Control * string * bool -> string

Public Function GetPostBackEventReference (control As Control, argument As String, registerForEventValidation As Boolean) As String

Parameters

control

Control

The server Control that processes the postback on the server.

argument

String

A string of optional arguments to pass to control.

registerForEventValidation

Boolean

true to register the event reference for validation; otherwise, false.

Returns

String

A string that, when treated as script on the client, initiates the postback.

Exceptions

ArgumentNullException

The specified Control is null.

Remarks

To implement the IPostBackEventHandler interface for a Page, use the @ Implements directive.

The GetPostBackEventReference method can be used with the Button control when the UseSubmitBehavior property is false. In this scenario, the GetPostBackEventReference method returns the client postback event for the Button control.

If registerForEventValidation is true, the GetPostBackEventReference(PostBackOptions, Boolean) method calls the RegisterForEventValidation(String, String) method to register the event reference for validation with a unique control ID that represents the client control that is generating the event.

See also

• PostBackOptions
• IPostBackEventHandler
• Client Callbacks Without Postbacks in ASP.NET Pages

GetPostBackEventReference(PostBackOptions, Boolean)

Returns a string that can be used in a client event to cause postback to the server. The reference string is defined by the specified PostBackOptions object. Optionally, registers the event reference for validation.

public:
 System::String ^ GetPostBackEventReference(System::Web::UI::PostBackOptions ^ options, bool registerForEventValidation);

public string GetPostBackEventReference (System.Web.UI.PostBackOptions options, bool registerForEventValidation);

member this.GetPostBackEventReference : System.Web.UI.PostBackOptions * bool -> string

Public Function GetPostBackEventReference (options As PostBackOptions, registerForEventValidation As Boolean) As String

Parameters

options

PostBackOptions

A PostBackOptions that defines the postback.

registerForEventValidation

Boolean

true to register the event reference for validation; otherwise, false.

Returns

String

A string that, when treated as script on the client, initiates the client postback.

Exceptions

ArgumentNullException

The PostBackOptions is null.

Remarks

To implement the IPostBackEventHandler interface for a Page object, use the @ Implements directive.

The GetPostBackEventReference method can be used with the Button control when the UseSubmitBehavior property is false. In this scenario, the GetPostBackEventReference method returns the client postback event for the Button control.

If registerForEventValidation is true, the GetPostBackEventReference(PostBackOptions, Boolean) method calls the RegisterForEventValidation(String, String) method to register the event reference for validation with a unique control ID that represents the client control that is generating the event.

See also

• PostBackOptions
• IPostBackEventHandler
• Button
• Client Callbacks Without Postbacks in ASP.NET Pages

GetPostBackEventReference(PostBackOptions)

Returns a string that can be used in a client event to cause postback to the server. The reference string is defined by the specified PostBackOptions instance.

public:
 System::String ^ GetPostBackEventReference(System::Web::UI::PostBackOptions ^ options);

public string GetPostBackEventReference (System.Web.UI.PostBackOptions options);

member this.GetPostBackEventReference : System.Web.UI.PostBackOptions -> string

Public Function GetPostBackEventReference (options As PostBackOptions) As String

Parameters

options

PostBackOptions

A PostBackOptions that defines the postback.

Returns

String

A string that, when treated as script on the client, initiates the client postback.

Exceptions

ArgumentNullException

The PostBackOptions parameter is null

Remarks

To implement the IPostBackEventHandler interface for a Page, use the @ Implements directive.

The GetPostBackEventReference method can be used with the Button control when the UseSubmitBehavior property is false. In this scenario, the GetPostBackEventReference method returns the client postback event for the Button control.

See also

• PostBackOptions
• IPostBackEventHandler
• Button
• Client Callbacks Without Postbacks in ASP.NET Pages

GetPostBackEventReference(Control, String)

Returns a string that can be used in a client event to cause postback to the server. The reference string is defined by the specified control that handles the postback and a string argument of additional event information.

public:
 System::String ^ GetPostBackEventReference(System::Web::UI::Control ^ control, System::String ^ argument);

public string GetPostBackEventReference (System.Web.UI.Control control, string argument);

member this.GetPostBackEventReference : System.Web.UI.Control * string -> string

Public Function GetPostBackEventReference (control As Control, argument As String) As String

Parameters

control

Control

The server Control that processes the postback on the server.

argument

String

A string of optional arguments to pass to the control that processes the postback.

Returns

String

A string that, when treated as script on the client, initiates the postback.

Exceptions

ArgumentNullException

The specified Control is null.

Examples

The following code example demonstrates the use of the GetPostBackEventReference method. The custom control, MyControl, implements the IPostBackEventHandler interface. When the button on the page is clicked, the RaisePostBackEvent method of the custom control is invoked.

<%@ 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">

  public class MyControl : Label, IPostBackEventHandler
  {

    // Use the constructor to defined default label text.
    public MyControl()
    {
      base.Text = "No postback raised.";
    }
    
    // Implement the RaisePostBackEvent method from the
    // IPostBackEventHandler interface. 
    public void RaisePostBackEvent(string eventArgument)
    {
      base.Text = "Postback handled by " + this.ID.ToString() + ". <br/>" +
                  "Postback caused by " + eventArgument.ToString() + ".";
      
    }
  }

  protected void Page_Load(object sender, EventArgs e)
  {
    // Get a ClientScriptManager reference from the Page class.
    ClientScriptManager cs = Page.ClientScript;

    // Create an instance of the custom label control and 
    // add it to the page.
    MyControl mycontrol = new MyControl();
    mycontrol.ID = "mycontrol1";
    PlaceHolder1.Controls.Add(mycontrol);
    PlaceHolder1.Controls.Add(new LiteralControl("<br/>"));
    
    // Create a button element with its onClick attribute defined
    // to create a postback event reference to the custom label control.
    HtmlInputButton b = new HtmlInputButton();
    b.ID = "mybutton1";
    b.Value = "Click";
    b.Attributes.Add("onclick", cs.GetPostBackEventReference(mycontrol, b.ID.ToString()));
    PlaceHolder1.Controls.Add(b);
    PlaceHolder1.Controls.Add(new LiteralControl("<br/>"));
    
    // Create a link element with its href attribute defined
    // to create a postback event reference to the custom label control.
    HtmlAnchor a = new HtmlAnchor();
    a.ID = "myanchor1";
    a.InnerText = "link";
    a.HRef = cs.GetPostBackClientHyperlink(mycontrol, a.ID.ToString());
    PlaceHolder1.Controls.Add(a);
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>ClientScriptManager Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <asp:PlaceHolder id="PlaceHolder1" 
                       runat="server">
      </asp:PlaceHolder>
    </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">
  
  Public Class MyControl
    Inherits Label
    Implements IPostBackEventHandler
     
    Public Sub New()
      
      MyBase.Text = "No postback raised."
    
    End Sub
    
    Public Sub RaisePostBackEvent(ByVal eventArgument As String) Implements System.Web.UI.IPostBackEventHandler.RaisePostBackEvent
      
      MyBase.Text = "Postback handled by " & Me.ID.ToString() & ". <br/>" & _
                "Postback caused by " + eventArgument.ToString() & "."

    End Sub
    
  End Class
   

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

    ' Get a ClientScriptManager reference from the Page class.
    Dim cs As ClientScriptManager = Page.ClientScript

    ' Create an instance of the custom label control and 
    ' add it to the page.
    Dim mycontrol As New MyControl()
    MyControl.ID = "mycontrol1"
    PlaceHolder1.Controls.Add(MyControl)
    PlaceHolder1.Controls.Add(New LiteralControl("<br/>"))
    
    ' Create a button element with its onClick attribute defined
    ' to create a postback event reference to the custom label control.
    Dim b As New HtmlInputButton()
    b.ID = "mybutton1"
    b.Value = "Click"
    b.Attributes.Add("onclick", cs.GetPostBackEventReference(MyControl, b.ID.ToString()))
    PlaceHolder1.Controls.Add(b)
    PlaceHolder1.Controls.Add(New LiteralControl("<br/>"))
    
    ' Create a link element with its href attribute defined
    ' to create a postback event reference to the custom label control.
    Dim a As New HtmlAnchor()
    a.ID = "myanchor1"
    a.InnerText = "link"
    a.HRef = cs.GetPostBackClientHyperlink(MyControl, a.ID.ToString())
    PlaceHolder1.Controls.Add(a)
    
  End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>ClientScriptManager Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <asp:PlaceHolder id="PlaceHolder1" 
                       runat="server">
      </asp:PlaceHolder>
    </div>
    </form>
</body>
</html>

The following code example has the same functionality as the preceding one, except that instead of a custom control, the Page class implements the IPostBackEventHandler interface.

<%@ Page Language="C#"  %>
<%@ Implements Interface="System.Web.UI.IPostBackEventHandler" %>

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

<script runat="server">
  
  public void RaisePostBackEvent(string eventArgument)
  {
    Label1.Text = "Postback handled by " + this.ID.ToString() + ". <br/>" +
                  "Postback caused by " + eventArgument.ToString() + "."; ;
  }
  
  protected void Page_Load(object sender, EventArgs e)
  {
    // Get a ClientScriptManager reference from the Page class.
    ClientScriptManager cs = Page.ClientScript;
    
    // Create a button element with its onClick attribute defined
    // to create a postback event reference to the custom label control.
    HtmlInputButton b = new HtmlInputButton();
    b.ID = "mybutton1";
    b.Value = "Click";
    b.Attributes.Add("onclick", cs.GetPostBackEventReference(this, b.ID.ToString()));
    PlaceHolder1.Controls.Add(b);
    PlaceHolder1.Controls.Add(new LiteralControl("<br/>"));
    
    // Create a link element with its href attribute defined
    // to create a postback event reference to the custom label control.
    HtmlAnchor a = new HtmlAnchor();
    a.ID = "myanchor1";
    a.InnerText = "link";
    a.HRef = cs.GetPostBackClientHyperlink(this, a.ID.ToString());
    PlaceHolder1.Controls.Add(a);
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>ClientScriptManager Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <asp:Label id="Label1"
                 runat="server" />
      <br />
      <asp:PlaceHolder id="PlaceHolder1" 
                       runat="server">
      </asp:PlaceHolder>
    </div>
    </form>
</body>
</html>

<%@ Page Language="VB" %>
<%@ Implements Interface="System.Web.UI.IPostBackEventHandler" %>

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

<script runat="server">
 
  Public Sub RaisePostBackEvent(ByVal eventArgument As String) _
    Implements IPostBackEventHandler.RaisePostBackEvent
    
    Label1.Text = "Postback handled by " & Me.ID.ToString() & ". <br/>" & _
           "Postback caused by " + eventArgument.ToString() & "."
  
  End Sub
  

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

    ' Get a ClientScriptManager reference from the Page class.
    Dim cs As ClientScriptManager = Page.ClientScript
    
    ' Create a button element with its onClick attribute defined
    ' to create a postback event reference to the custom label control.
    Dim b As New HtmlInputButton()
    b.ID = "mybutton1"
    b.Value = "Click"
    b.Attributes.Add("onclick", cs.GetPostBackEventReference(Me, b.ID.ToString()))
    PlaceHolder1.Controls.Add(b)
    PlaceHolder1.Controls.Add(New LiteralControl("<br/>"))
    
    ' Create a link element with its href attribute defined
    ' to create a postback event reference to the custom label control.
    Dim a As New HtmlAnchor()
    a.ID = "myanchor1"
    a.InnerText = "link"
    a.HRef = cs.GetPostBackClientHyperlink(Me, a.ID.ToString())
    PlaceHolder1.Controls.Add(a)
    
  End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>ClientScriptManager Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <asp:Label id="Label1"
                 runat="server" />
      <br />
      <asp:PlaceHolder id="PlaceHolder1" 
                       runat="server">
      </asp:PlaceHolder>
    </div>
    </form>
</body>
</html>

Remarks

To implement the IPostBackEventHandler interface for a Page, use the @ Implements directive.

The GetPostBackEventReference method can be used with the Button control when the UseSubmitBehavior property is false. In this scenario, the GetPostBackEventReference method returns the client postback event for the Button control.

See also

• PostBackOptions
• IPostBackEventHandler
• Client Callbacks Without Postbacks in ASP.NET Pages