Page.IsStartupScriptRegistered(String) 方法

定义

注意

The recommended alternative is ClientScript.IsStartupScriptRegistered(string key). http://go.microsoft.com/fwlink/?linkid=14202

确定 Page 对象是否注册了客户端启动脚本。Determines whether the client startup script is registered with the Page object.

public:
 bool IsStartupScriptRegistered(System::String ^ key);
public bool IsStartupScriptRegistered (string key);
[System.Obsolete("The recommended alternative is ClientScript.IsStartupScriptRegistered(string key). http://go.microsoft.com/fwlink/?linkid=14202")]
public bool IsStartupScriptRegistered (string key);
member this.IsStartupScriptRegistered : string -> bool
[<System.Obsolete("The recommended alternative is ClientScript.IsStartupScriptRegistered(string key). http://go.microsoft.com/fwlink/?linkid=14202")>]
member this.IsStartupScriptRegistered : string -> bool
Public Function IsStartupScriptRegistered (key As String) As Boolean

参数

key
String

要搜索的启动脚本的字符串关键字。The string key of the startup script to search for.

返回

Boolean

如果注册了启动脚本,则为 true;否则为 falsetrue if the startup script is registered; otherwise, false.

属性

示例

下面的代码示例演示如何将 RegisterStartupScript 方法与方法结合使用 IsStartupScriptRegisteredThe following code example demonstrates the use of the RegisterStartupScript method in conjunction with the IsStartupScriptRegistered method. 如果代码声明块中编写的 ECMAScript 尚未注册(由确定 IsStartupScriptRegistered ),则 RegisterStartupScript 发出调用。If the ECMAScript written in the code declaration block has not already been registered, as determined by IsStartupScriptRegistered, then a RegisterStartupScript call is made.

<%@ 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)
  {
    String csname1 = "PopupScript";
    String csname2 = "ButtonClickScript";

    if (!IsClientScriptBlockRegistered(csname1))
    {
        String cstext1 = "<script type=\"text/javascript\">" +
            "alert('Hello World');</" + "script>";
        RegisterStartupScript(csname1, cstext1);
    }

    if (!IsClientScriptBlockRegistered(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>");
      RegisterClientScriptBlock(csname2, cstext2.ToString());
    }
  }
</script>
<html  >
  <head>
    <title>RegisterClientScriptBlock 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 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.'} </")
            cstext2.Append("script>")
            RegisterClientScriptBlock(csname2, cstext2.ToString())
        End If
    End Sub
</script>
<html  >
  <head>
    <title>RegisterClientScriptBlock Example</title>
  </head>
  <body>
     <form id="Form1"
         runat="server">
        <input type="text" id="Message" /> <input type="button" value="ClickMe" onclick="DoClick()" />
     </form>
  </body>
</html>

注解

在调用之前调用此方法 Page.RegisterStartupScript ,以避免不必要地汇编客户端脚本。Call this method before calling Page.RegisterStartupScript to avoid unnecessarily assembling the client-side script. 如果脚本需要创建大量的服务器资源,则这一点特别重要。This is particularly important if the script requires a large amount of server resources to create.

IsStartupScriptRegistered 方法已弃用。The IsStartupScriptRegistered method has been deprecated. 使用 IsStartupScriptRegistered 类中的方法 ClientScriptManagerUse the IsStartupScriptRegistered method in the ClientScriptManager class.

适用于

另请参阅