ScriptManager.RegisterStartupScript Method (Control, Type, String, String, Boolean)


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Registers a startup script block for a control that is inside an UpdatePanel by using the ScriptManager control, and adds the script block to the page.

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

public static void RegisterStartupScript(
	Control control,
	Type type,
	string key,
	string script,
	bool addScriptTags


Type: System.Web.UI.Control

The control that is registering the client script block.

Type: System.Type

The type of the client script block. This parameter is usually specified by using the typeof operator (C#) or the GetType operator (Visual Basic) to retrieve the type of the control that is registering the script.

Type: System.String

A unique identifier for the script block.

Type: System.String

The script to register.

Type: System.Boolean

true to enclose the script block with <script> and </script> tags; otherwise, false.

Exception Condition

control is null.

- or -

type is null.


control is not in the page's control tree.

You use the RegisterStartupScript method to register a startup script block for a page that is compatible with partial-page rendering and that has no Microsoft Ajax Library dependencies. Startup script blocks that are registered by using this method are sent to the page only when the control that is registering the block is inside an UpdatePanel control that is being updated. To register a startup script block every time that an asynchronous postback occurs, use the RegisterStartupScript(Page, Type, String, String, Boolean) overload of this method.

If you want to register a startup script that does not pertain to partial-page updates, and if you want to register the script only one time during initial page rendering, use the RegisterStartupScript method of the ClientScriptManager class. You can get a reference to the ClientScriptManager object from the ClientScript property of the page.

The script block that is rendered by the RegisterStartupScript method executes when the page finishes loading but before the page's client onload event is raised. Startup script blocks are located at the bottom of the rendered ASP.NET page just before the </form> tag.

Startup script blocks that are registered by using RegisterStartupScript are not guaranteed to be output in the same order in which they are registered. If the order of the startup script blocks is important, use a StringBuilder object to gather the script blocks in a single string, and then register them all as a single startup script.

.NET Framework
Available since 3.5
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