ClientScriptManager.RegisterStartupScript Method

Definition

Registers the startup script with the Page object.

Overloads

RegisterStartupScript(Type, String, String)

Registers the startup script with the Page object using a type, a key, and a script literal.

RegisterStartupScript(Type, String, String, Boolean)

Registers the startup script with the Page object using a type, a key, a script literal, and a Boolean value indicating whether to add script tags.

RegisterStartupScript(Type, String, String)

Registers the startup script with the Page object using a type, a key, and a script literal.

public:
 void RegisterStartupScript(Type ^ type, System::String ^ key, System::String ^ script);
public void RegisterStartupScript (Type type, string key, string script);
member this.RegisterStartupScript : Type * string * string -> unit
Public Sub RegisterStartupScript (type As Type, key As String, script As String)

Parameters

type
Type

The type of the startup script to register.

key
String

The key of the startup script to register.

script
String

The startup script literal to register.

Examples

The following code example demonstrates the use of the RegisterStartupScript method. Note that the beginning and closing script tags are included within the script parameter. To have the script tags added based on an additional parameter setting, see the RegisterStartupScript method.

<%@ 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 void Page_Load(Object sender, EventArgs e)
  {
    // Define the name and type of the client scripts on the page.
    String csname1 = "PopupScript";
    Type cstype = this.GetType();
        
    // Get a ClientScriptManager reference from the Page class.
    ClientScriptManager cs = Page.ClientScript;

    // Check to see if the startup script is already registered.
    if (!cs.IsStartupScriptRegistered(cstype, csname1))
    {
        StringBuilder cstext1 = new StringBuilder();
        cstext1.Append("<script type=text/javascript> alert('Hello World!') </");
        cstext1.Append("script>");

        cs.RegisterStartupScript(cstype, csname1, cstext1.ToString());
    }
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>RegisterStartupScript</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    
    </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 Sub Page_Load(ByVal sender As [Object], ByVal e As EventArgs)
        ' Define the name and type of the client scripts on the page. 
        Dim csname1 As [String] = "PopupScript"
        Dim cstype As Type = Me.[GetType]()
    
        ' Get a ClientScriptManager reference from the Page class. 
        Dim cs As ClientScriptManager = Page.ClientScript
    
        ' Check to see if the startup script is already registered. 
        If Not cs.IsStartupScriptRegistered(cstype, csname1) Then
            Dim cstext1 As New StringBuilder()
            cstext1.Append("<script type=text/javascript> alert('Hello World!') </")
            cstext1.Append("script>")
        
            cs.RegisterStartupScript(cstype, csname1, cstext1.ToString())
        End If
    End Sub

</script>

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

Remarks

A client script is uniquely identified by its key and its type. Scripts with the same key and type are considered duplicates. Only one script with a given type and key pair can be registered with the page. Attempting to register a script that is already registered does not create a duplicate of the script.

Call the IsStartupScriptRegistered method to determine whether a startup script with a given key and type pair is already registered and avoid unnecessarily attempting to add the script.

In this overload of the RegisterStartupScript method, you must make sure that the script provided in the script parameter is wrapped with a <script> element block.

The script block added by the RegisterStartupScript method executes when the page finishes loading but before the page's OnLoad event is raised. The script blocks are not guaranteed to be output in the order they are registered. If the order of the script blocks is important, use a StringBuilder object to gather the scripts together in a single string, and then register them all in a single client script block.

See also

Applies to

RegisterStartupScript(Type, String, String, Boolean)

Registers the startup script with the Page object using a type, a key, a script literal, and a Boolean value indicating whether to add script tags.

public:
 void RegisterStartupScript(Type ^ type, System::String ^ key, System::String ^ script, bool addScriptTags);
public void RegisterStartupScript (Type type, string key, string script, bool addScriptTags);
member this.RegisterStartupScript : Type * string * string * bool -> unit
Public Sub RegisterStartupScript (type As Type, key As String, script As String, addScriptTags As Boolean)

Parameters

type
Type

The type of the startup script to register.

key
String

The key of the startup script to register.

script
String

The startup script literal to register.

addScriptTags
Boolean

A Boolean value indicating whether to add script tags.

Exceptions

type is null.

Examples

The following code example demonstrates the use of the RegisterStartupScript method. Note that the addScriptTags parameter is set to false so the beginning and closing script tags are included with the script parameter.

<%@ 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 void Page_Load(Object sender, EventArgs e)
  {
    // Define the name and type of the client scripts on the page.
    String csname1 = "PopupScript";
    String csname2 = "ButtonClickScript";
    Type cstype = this.GetType();
        
    // Get a ClientScriptManager reference from the Page class.
    ClientScriptManager cs = Page.ClientScript;

    // Check to see if the startup script is already registered.
    if (!cs.IsStartupScriptRegistered(cstype, csname1))
    {
      String cstext1 = "alert('Hello World');";
      cs.RegisterStartupScript(cstype, csname1, cstext1, true);
    }

    // Check to see if the client script is already registered.
    if (!cs.IsClientScriptBlockRegistered(cstype, csname2))
    {
      StringBuilder cstext2 = new StringBuilder();
      cstext2.Append("<script type=\"text/javascript\"> function DoClick() {");
      cstext2.Append("Form1.Message.value='Text from client script.'} </");
      cstext2.Append("script>");
      cs.RegisterClientScriptBlock(cstype, csname2, cstext2.ToString(), false);
    }
  }
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>ClientScriptManager Example</title>
  </head>
  <body>
     <form id="Form1"
         runat="server">
        <input type="text" id="Message" /> <input type="button" value="ClickMe" onclick="DoClick()" />
     </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">

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

    ' Define the name and type of the client scripts on the page.
    Dim csname1 As String = "PopupScript"
    Dim csname2 As String = "ButtonClickScript"
    Dim cstype As Type = Me.GetType()
    
    ' Get a ClientScriptManager reference from the Page class.
    Dim cs As ClientScriptManager = Page.ClientScript

    ' Check to see if the startup script is already registered.
    If (Not cs.IsStartupScriptRegistered(cstype, csname1)) Then
      
      Dim cstext1 As String = "alert('Hello World');"
      cs.RegisterStartupScript(cstype, csname1, cstext1, True)
      
    End If
    
    ' Check to see if the client script is already registered.
    If (Not cs.IsClientScriptBlockRegistered(cstype, csname2)) Then
      
      Dim cstext2 As New StringBuilder()
            cstext2.Append("<script type=""text/javascript""> function DoClick() {")
      cstext2.Append("Form1.Message.value='Text from client script.'} </")
      cstext2.Append("script>")
      cs.RegisterClientScriptBlock(cstype, csname2, cstext2.ToString(), False)
      
    End If
    
  End Sub
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>ClientScriptManager Example</title>
  </head>
  <body>
     <form id="Form1"
         runat="server">
        <input type="text" id="Message" /> <input type="button" value="ClickMe" onclick="DoClick()" />
     </form>
  </body>
</html>

Remarks

A startup script is uniquely identified by its key and its type. Scripts with the same key and type are considered duplicates. Only one script with a given type and key pair can be registered with the page. Attempting to register a script that is already registered does not create a duplicate of the script.

Call the IsStartupScriptRegistered method to determine whether a startup script with a given key and type pair is already registered and avoid unnecessarily attempting to add the script.

In this overload of the RegisterStartupScript method, you can indicate whether the script provided in the script parameter is wrapped with a <script> element block by using the addScriptTags parameter. Setting addScriptTags to true indicates that script tags will be added automatically.

The script block added by the RegisterStartupScript method executes when the page finishes loading but before the page's OnLoad event is raised. The script blocks are not guaranteed to be output in the order they are registered. If the order of the script blocks is important, use a StringBuilder object to gather the scripts together in a single string, and then register them all in a single client script block.

See also

Applies to