Page.IsStartupScriptRegistered(String) 方法

定義

命名空間:
System.Web.UI
組件:
System.Web.dll

警告

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

判斷用戶端啟動腳本是否已註冊於該 Page 物件。

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

參數

key
String

啟動腳本的字串鍵要搜尋。

傳回

Boolean

true如果啟動腳本已註冊;否則，。 false

屬性
ObsoleteAttribute

範例

以下範例說明了該方法與該RegisterStartupScript方法的結合使用IsStartupScriptRegistered。 若程式碼宣告區塊中撰寫的 ECMAScript 尚未註冊，依 判定 IsStartupScriptRegistered，則 RegisterStartupScript 會進行呼叫。

<%@ 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>

備註

在呼叫 Page.RegisterStartupScript 前先呼叫此方法，以避免不必要的組譯客戶端腳本。 如果腳本需要大量伺服器資源來建立，這點尤其重要。

方法 IsStartupScriptRegistered 已被取代。 在課堂上用這個 IsStartupScriptRegistered 方法 ClientScriptManager 。

適用於

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