的RegisterStartupScript和的RegisterClientScriptBlock之间的区别？

更新时间：2023-12-05 22:32:34

Here's一个老话题在我列出的主要差异，并在其中，你应该使用这些方法的条件。我想你可能会发现它有用经过讨论。

Here's an old discussion thread where I listed the main differences and the conditions in which you should use each of these methods. I think you may find it useful to go through the discussion.

要解释差异有关您张贴的例子：

To explain the differences as relevant to your posted example:

一个。当您使用的RegisterStartupScript ，它会使你的脚本的在的页面（表单的结束标记前右）的所有元素。这使得脚本调用或引用页面元素，没有它没有找到它们在页面的DOM的可能性。

a. When you use RegisterStartupScript, it will render your script after all the elements in the page (right before the form's end tag). This enables the script to call or reference page elements without the possibility of it not finding them in the Page's DOM.

下面是当你调用页面的呈现源的的RegisterStartupScript 方法：

Here is the rendered source of the page when you invoke the RegisterStartupScript method:

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1"><title></title></head>
<body>
    <form name="form1" method="post" action="StartupScript.aspx" id="form1">
        <div>
            <input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="someViewstategibberish" />
        </div>
        <div> <span id="lblDisplayDate">Label</span>
            <br />
            <input type="submit" name="btnPostback" value="Register Startup Script" id="btnPostback" />
            <br />
            <input type="submit" name="btnPostBack2" value="Register" id="btnPostBack2" />
        </div>
        <div>
            <input type="hidden" name="__EVENTVALIDATION" id="__EVENTVALIDATION" value="someViewstategibberish" />
        </div>
        <!-- Note this part -->
        <script language='javascript'>
            var lbl = document.getElementById('lblDisplayDate');
            lbl.style.color = 'red';
        </script>
    </form>
    <!-- Note this part -->
</body>
</html>

乙。当您使用的RegisterClientScriptBlock ，该脚本呈现的视图状态标记之后，但在任何一个页面元素。由于这是一个直接的脚本（不是函数，可以的名为的，它会立即由浏览器执行，但浏览器没有找到在页面的DOM标签在这个阶段，因此你应该收到未找到对象错误。

b. When you use RegisterClientScriptBlock, the script is rendered right after the Viewstate tag, but before any of the page elements. Since this is a direct script (not a function that can be called, it will immediately be executed by the browser. But the browser does not find the label in the Page's DOM at this stage and hence you should receive an "Object not found" error.

下面是当你调用页面的呈现源的的RegisterClientScriptBlock 方法：

Here is the rendered source of the page when you invoke the RegisterClientScriptBlock method:

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1"><title></title></head>
<body>
    <form name="form1" method="post" action="StartupScript.aspx" id="form1">
        <div>
            <input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="someViewstategibberish" />
        </div>
        <script language='javascript'>
            var lbl = document.getElementById('lblDisplayDate');
            // Error is thrown in the next line because lbl is null.
            lbl.style.color = 'green';

因此，要总结，你应该如果你打算呈现一个函数定义调用了后一种方法。然后，您可以渲染的调用该函数的用前一种方法（或添加客户端属性）。

Therefore, to summarize, you should call the latter method if you intend to render a function definition. You can then render the call to that function using the former method (or add a client side attribute).

意见后编辑：

有关例如，以下功能将工作：

For instance, the following function would work:

protected void btnPostBack2_Click(object sender, EventArgs e) 
{ 
  System.Text.StringBuilder sb = new System.Text.StringBuilder(); 
  sb.Append("<script language='javascript'>function ChangeColor() {"); 
  sb.Append("var lbl = document.getElementById('lblDisplayDate');"); 
  sb.Append("lbl.style.color='green';"); 
  sb.Append("}</script>"); 

  //Render the function definition. 
  if (!ClientScript.IsClientScriptBlockRegistered("JSScriptBlock")) 
  {
    ClientScript.RegisterClientScriptBlock(this.GetType(), "JSScriptBlock", sb.ToString()); 
  }

  //Render the function invocation. 
  string funcCall = "<script language='javascript'>ChangeColor();</script>"; 

  if (!ClientScript.IsStartupScriptRegistered("JSScript"))
  { 
    ClientScript.RegisterStartupScript(this.GetType(), "JSScript", funcCall); 
  } 
}

上一篇 : ：Windows服务每运行一小时

的RegisterStartupScript和的RegisterClientScriptBlock之间的区别？

相关阅读

推荐文章