Page.RegisterStartupScript Method (String, String)


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Note: This API is now obsolete.

Emits a client-side script block in the page response.

Namespace:   System.Web.UI
Assembly:  System.Web (in System.Web.dll)

<ObsoleteAttribute("The recommended alternative is ClientScript.RegisterStartupScript(Type type, string key, string script).")>
Public Overridable Sub RegisterStartupScript (
	key As String,
	script As String


Type: System.String

Unique key that identifies a script block.

Type: System.String

Content of script that will be sent to the client.

Similar to the RegisterClientScriptBlock method, the RegisterStartupScript method emits the script just before the closing tag of the Page object's <form runat= server> element. Be sure to include opening and closing <script> elements around the script block string specified in the script parameter.

Because this method uses a key to identify the script block, the script block does not have to be emitted to the output stream each time it is requested by a different server control instance

Any script blocks with the same key parameter values are considered duplicates.


Remember to include HTML comment tags around your script so that it will not be rendered if the requesting browser does not support scripts.

The RegisterStartupScript method has been deprecated. Use the RegisterStartupScript method in the ClientScriptManager class instead.

The following code example demonstrates the use of the RegisterStartupScript method in conjunction with the IsStartupScriptRegistered method. If the ECMAScript written in the code declaration block has not already been registered, as determined by the IsStartupScriptRegistered method, then a RegisterStartupScript call is made.

<%@ Page Language="VB"  %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "">

<script runat="server">
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
        Dim csname1 As String = "PopupScript"

        Dim csname2 As String = "ButtonClickScript"

        If Not IsClientScriptBlockRegistered(csname1) Then
            Dim cstext1 As String = "<script type=""text/javascript"">" & _
                "alert('Hello World');</" & "script>"
            RegisterStartupScript(csname1, cstext1)
        End If

        If Not IsClientScriptBlockRegistered(csname2) Then
            Dim cstext2 As New StringBuilder()
            cstext2.Append("<script type=""text/javascript""> function DoClick() {")
            cstext2.Append("Form1.Message.value='Text from client script.'} </")
            RegisterClientScriptBlock(csname2, cstext2.ToString())
        End If
    End Sub
<html  >
    <title>RegisterClientScriptBlock Example</title>
     <form id="Form1"
        <input type="text" id="Message" /> <input type="button" value="ClickMe" onclick="DoClick()" />

.NET Framework
Available since 1.1
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