JavaScript 不起作用(自定义对话框）

按照本教程，

自定义对话框

我已经为 ASP.Net 页面提供了 3 个 asp 内容占位符，他们猜他们已经在使用某种脚本，这在这里没有问题。

问题是，我能够使用"OnClientClick"属性调用函数，但该函数在不同的.js文件中具有更多函数。如果我在调用其他函数之前放置警报，它可以工作，但在它进入我的第一个函数之后就不行了。

教程列出了所有 javascript 代码，这是我在 ASP.Net 内容位置使用它的代码，

<asp:Content ID="Content4" ContentPlaceHolderID="cphSubmit" runat="server">
 <script type="text/javascript" src="/_layouts/1033/jquery.js"></script>
 <script type="text/javascript" language="JavaScript" src="CustomDialog.js"></script>
 <script type="text/javascript" language="JavaScript">
        function ShowMessage()
        {
            alert("1");
            SetText('Yes','No');
            alert("2");
            DisplayConfirmMessage('are you sure',180,90)
            SetDefaultButton('btnConfOK');
            return false;
        }
 </script>
            <div id="divConfMessage" runat="server" style="BORDER-RIGHT:black thin solid; BORDER-TOP:black thin solid; DISPLAY:none; Z-INDEX:200; BORDER-LEFT:black thin solid; BORDER-BOTTOM:black thin solid">
            <div style="BACKGROUND-COLOR: #6699cc;TEXT-ALIGN: center" id="confirmText">
            </div>
            <div style="Z-INDEX: 105;HEIGHT: 2%;BACKGROUND-COLOR: white;TEXT-ALIGN: center">
            </div>
            <div style="Z-INDEX: 105;BACKGROUND-COLOR: white;TEXT-ALIGN: center">
                <asp:Button ID="btnConfOK" Runat="server" Text="OK"></asp:Button>
                <asp:Button ID="btnConfCancel" Runat="server" Text="Cancel"></asp:Button>
            </div>
        </div>
<hr />

    <asp:Button ID="btDelete" runat="server" 
    OnClientClick="ShowMessage();"
    Text="Delete" UseSubmitBehavior="False" Width="200px"  />

我删除了目前拥有的其他一些控件，它显示警报"1"但未达到"2"，

这是自定义对话框脚本，

var divWidth = '';
var divHeight = '';
var txtFirstButton = 'OK';
var txtSecondButton = 'Cancel'
    function DisplayConfirmMessage(msg,width,height)
    {
            // Set default dialogbox width if null
            if(width == null)
            divWidth = 180 
            else 
            divWidth = width;
            // Set default dialogBox height if null
            if(height == null)
            divHeight = 90 
            else 
            divHeight = height;

            // Ge the dialogbox object
            var divLayer = document.getElementById('divConfMessage');
            // Set dialogbox height and width
            SetHeightWidth(divLayer)
            // Set dialogbox top and left
            SetTopLeft(divLayer);
            // Show the div layer
            divLayer.style.display = 'block';
            // Change the location and reset the width and height if window is resized
            window.onresize = function() { if(divLayer.style.display == 'block'){ SetTopLeft(divLayer); SetHeightWidth(divLayer)}}
            // Set the dialogbox display message
            document.getElementById('confirmText').innerText = msg;
    }
    function SetTopLeft(divLayer)
    {
        // Get the dialogbox height
        var divHeightPer = divLayer.style.height.split('px')[0];
         // Set the top variable 
        var top = (parseInt(document.body.offsetHeight)/ 2) - (divHeightPer/2)
        // Get the dialog box width
        var divWidthPix = divLayer.style.width.split('px')[0];
        // Get the left variable
        var left = (parseInt(document.body.offsetWidth)/2) - (parseInt(divWidthPix)/2);
        // set the dialogbox position to abosulute
        divLayer.style.position = 'absolute';
        // Set the div top to the height 
        divLayer.style.top = top
        // Set the div Left to the height 
        divLayer.style.left = left;
    }
    function SetHeightWidth(divLayer)
    {
        // Set the dialogbox width
        divLayer.style.width = divWidth + 'px';
        // Set the dialogbox Height
        divLayer.style.height = divHeight + 'px'
    }
    function SetText(txtButton1,txtButton2)
    {
            // Set display text for the two buttons
            if(txtButton1 == null)
            document.getElementById('btnConfOK').innerText = txtFirstButton;
            else
            document.getElementById('btnConfOK').innerText = txtButton1;
                            // Set display text for the two buttons
            if(txtButton2 == null)
            document.getElementById('btnConfCancel').innerText = txtSecondButton;
            else
            document.getElementById('btnConfCancel').innerText = txtButton2;
    }
    function SetDefaultButton(defaultButton)
    {
            // Set the focus on the Cancel button
            document.getElementById(defaultButton).focus();
    }

刚刚注意到它上升到这个功能

function SetText(txtButton1,txtButton2)
    {
            alert("2");
            // Set display text for the two buttons

然后它丢失了，它试图从 txtButton1 获取值，这可能意味着我的 ASPX 页面中的 Div 标签没有正确呈现:(

                if(txtButton1 == null)
            document.getElementById('btnConfOK').innerText = txtFirstButton;
            else
            document.getElementById('btnConfOK').innerText = txtButton1;
            alert("3");

*编辑*如果我删除 SetText 函数，它确实会显示，但它不会触发我的"OnClick"方法，只是刷新页面***

        <asp:Button ID="Button1" runat="server" CausesValidation="False" CssClass="gradientbutton"
    OnClick="btDelete_Click" OnClientClick="ShowMessage();this.disabled=true;this.value='Wait...';"
    Text="Delete" UseSubmitBehavior="False" Width="200px"  />

刚刚意识到在页面上出现错误，即使它显示确认框

说 findElementbyid(..( 是空或不是对象