javascript getelementbyid无效,因为id已更改

Question

好吧我想得到一个文本框的价值,但当我做javascript代码getElementByID()的事情,文本框的ID从原始值改变了如何我现在得到它？我甚至尝试将cliendIdMode ="静态"放入不起作用.

<script type="text/javascript" language="javascript">
    function uploadFileChange() {
        var tbox = document.getElementById('txtFileName').value;
        var fu = document.getElementById("FileUpload1").value;
        if (tbox != fu) {
            document.getElementById('txtFileName').value = document.getElementById("FileUpload1").value;
        }
        return false;
    }
</script>

原始文本框是:

<asp:TextBox ID="txtFileName" CssClass="textbox" ClientIDMode="Static" runat="server"
                        Width="300px" ReadOnly="true" />

但后来成了:

<input name="fuFileInfo$txtFileName" type="text" readonly="readonly" id="fuFileInfo_txtFileName" class="textbox" ClientIDMode="Static" onclick="fuFileInfo_FileUpload1.click();return false;" style="width:300px;" />

Answer 1

ASP.NET将ID与服务器端标记的呈现方式不同.

因此,用于ClientID获取呈现的ID:

var tbox = document.getElementById('<%=txtFileName.ClientID %>').value;
var fu = document.getElementById('<%=FileUpload1.ClientID %>').value;