PostBackOptions Class

Reference

Definition

Namespace:: System.Web.UI

Assembly:: System.Web.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Specifies how client-side JavaScript is generated to initiate a postback event.

public ref class PostBackOptions sealed

public sealed class PostBackOptions

type PostBackOptions = class

Public NotInheritable Class PostBackOptions

Inheritance: Object
PostBackOptions

Examples

The following code example uses the OnClick event of a Button control to generate client-side script for a HyperLink control that will allow the HyperLink control to cause a postback event. Because the ActionUrl property of the myPostBackOptions object is set to "Page2.aspx", the postback will post the Web Forms page to another page named "Page2.aspx", which is not provided here. To use this example, you must add another Web page named "Page2.aspx" to your project or directory.

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class postbackoptionscs : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (Page.IsPostBack)
        {
            Label1.Text = "A postback event has occurred.";
        }
    }

    protected void Button1_Click(object sender, EventArgs e)
    {
        // Create a new PostBackOptions object and set its properties.
        PostBackOptions myPostBackOptions = new PostBackOptions(this);
        myPostBackOptions.ActionUrl = "Page2.aspx";
        myPostBackOptions.AutoPostBack = false;
        myPostBackOptions.RequiresJavaScriptProtocol = true;
        myPostBackOptions.PerformValidation = true;

        // Add the client-side script to the HyperLink1 control.
        HyperLink1.NavigateUrl = Page.ClientScript.GetPostBackEventReference(myPostBackOptions);

        Label1.Text = "Click this hyperlink to initiate a postback event.";
    }
}

Partial Class postbackoptionsvb
    Inherits System.Web.UI.Page
    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)

        ' Create a new PostBackOptions object and set its properties.
        Dim myPostBackOptions As PostBackOptions = New PostBackOptions(Me)
        myPostBackOptions.ActionUrl = "Page2.aspx"
        myPostBackOptions.AutoPostBack = False
        myPostBackOptions.RequiresJavaScriptProtocol = True
        myPostBackOptions.PerformValidation = True

        ' Add the client-side script to the HyperLink1 control.
        HyperLink1.NavigateUrl = Page.ClientScript.GetPostBackEventReference(myPostBackOptions)

        Label1.Text = "Click this hyperlink to initiate a postback event."

    End Sub

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

        If Page.IsPostBack Then
            Label1.Text = "A postback event has occurred."
        End If

    End Sub
End Class

The following code example is a Web page that can be used to run the preceding code-behind file.

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="postbackoptions.aspx.cs" Inherits="postbackoptionscs" %>

<!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 id="Head1" runat="server">
    <title>PostBackOptions Example</title>
  </head>
  <body>
    <form id="form1" runat="server">
    <h3>PostBackOptions Example Page</h3>
      Click this button to create client-side script for the 
      Postback hyperlink that causes a postback event to occur.
      <br />
      <asp:Button id="Button1" 
        runat="server" 
        text="Create Script" 
        onclick="Button1_Click" />
      <br /><br />
      <asp:Label id="Label1" 
        runat="server" 
        text="">
      </asp:Label>
      <br />
      <asp:HyperLink id="HyperLink1" 
        runat="server" 
        text="Postback">
      </asp:HyperLink>
    </form>
  </body>
</html>

<%@ Page Language="VB" AutoEventWireup="true" CodeFile="postbackoptions.aspx.vb" Inherits="postbackoptionsvb" %>

<!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 id="Head1" runat="server">
    <title>PostBackOptions Example</title>
  </head>
  <body>
    <form id="form1" runat="server">
    <h3>PostBackOptions Example Page</h3>
      Click this button to create client-side script for the 
      Postback hyperlink that causes a postback event to occur.
      <br />
      <asp:Button id="Button1" 
        runat="server" 
        text="Create Script" 
        onclick="Button1_Click" />
      <br /><br />
      <asp:Label id="Label1" 
        runat="server" 
        text=""></asp:Label>
      <br />
      <asp:HyperLink id="HyperLink1" 
        runat="server" 
        text="Postback"></asp:HyperLink>
      <br />
    </form>
  </body>
</html>

Remarks

The PostBackOptions class allows controls to emit client-side script that initiates a postback event. The PostBackOptions class also provides a reference to the control that initiated the postback event through the TargetControl property. The postback event is created based on the options specified in the PostBackOptions object passed in to the ClientScriptManager.GetPostBackEventReference method.

Normally, a postback to the server is initiated by elements such as a Submit button or an Image button. However, by emitting client-side JavaScript, different controls can initiate a postback event.

Constructors

PostBackOptions(Control)	Initializes a new instance of the PostBackOptions class with the specified target control data.
PostBackOptions(Control, String)	Initializes a new instance of the PostBackOptions class with the specified target control and argument data.
PostBackOptions(Control, String, String, Boolean, Boolean, Boolean, Boolean, Boolean, String)	Initializes a new instance of the PostBackOptions class with the specified values for the instance's properties.

Properties

ActionUrl	Gets or sets the target URL for the postback of a Web Forms page.
Argument	Gets or sets an optional argument that is transferred in the postback event.
AutoPostBack	Gets or sets a value that indicates whether the form will automatically post back to the server in response to a user action.
ClientSubmit	Gets or sets a value indicating whether the postback event should occur from client-side script.
PerformValidation	Gets or sets a value indicating whether client-side validation is required before the postback event occurs.
RequiresJavaScriptProtocol	Gets or sets a value indicating whether the `javascript:` prefix is generated for the client-side script.
TargetControl	Gets the control target that receives the postback event.
TrackFocus	Gets or sets a value indicating whether the postback event should return the page to the current scroll position and return focus to the current control.
ValidationGroup	Gets or sets the group of controls for which the PostBackOptions object causes validation when it posts back to the server.

Methods

Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)

Applies to

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