In this article I will explain how the issue that ASP.Net AJAX Control Tookit WaterMarkExtender control does not work for TextBox with TextMode Password.
To solve this issue I have built a jQuery WaterMark pluin which can set Watermark text ASP.Net TextBoxes in SingleLine, MultiLine and Password using jQuery Watermark plugin
 
HTML Markup
In the below HTML Markup I have ASP.Net TextBoxes with different TextMode i.e. SingleLine, MultiLine and Password i.e. Normal TextBox, TextArea and Password fields. You will notice that I have set ToolTip property of the TextBox, the text in the ToolTip property will be displayed as the Watermark text.
 
UserName:
<asp:TextBox ID="txtUserName" runat="server" ToolTip="Enter UserName">asp:TextBox><br />
Password:
<asp:TextBox ID="txtPassword" runat="server" TextMode="Password" ToolTip="Enter Password">asp:TextBox><br />
Email:
<asp:TextBox ID="txtEmail" runat="server" ToolTip="Enter Email">asp:TextBox><br />
Details:
<asp:TextBox ID="txtDetails" runat="server" TextMode="MultiLine" ToolTip="Enter Details">asp:TextBox>
 
 
Applying Watermark to ASP.Net TextBoxes
I have built the jQuery Watermark plugin to apply Watermark to all types of ASP.Net TextBoxes i.e. SingleLine, MultiLine and Password.
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js">script>
<script src="WaterMark.min.js" type="text/javascript">script>
<script type="text/javascript">
    $(function () {
        $("[id*=txtUserName], [id*=txtPassword], [id*=txtDetails]").WaterMark();
 
        //To change the color of Watermark
        $("[id*=Email]").WaterMark(
        {
            WaterMarkTextColor: '#000'
        });
    });
script>
 
 
The Watermark jQuery plugin has an optional property WaterMarkTextColor which can be used to set the color of the Watermark text.
The complete page HTML markup is provided below
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js">script>
<script src="WaterMark.min.js" type="text/javascript">script>
<script type="text/javascript">
    $(function () {
        $("[id*=txtUserName], [id*=txtPassword], [id*=txtDetails]").WaterMark();
 
        //To change the color of Watermark
        $("[id*=Email]").WaterMark(
        {
            WaterMarkTextColor: '#000'
        });
    });
script>
head>
<body>
    <form id="form1" runat="server">
    UserName:
    <asp:TextBox ID="txtUserName" runat="server" ToolTip="Enter UserName">asp:TextBox><br />
    Password:
    <asp:TextBox ID="txtPassword" runat="server" TextMode="Password" ToolTip="Enter Password">asp:TextBox><br />
    Email:
    <asp:TextBox ID="txtEmail" runat="server" ToolTip="Enter Email">asp:TextBox><br />
    Details:
    <asp:TextBox ID="txtDetails" runat="server" TextMode="MultiLine" ToolTip="Enter Details">asp:TextBox><br />
    form>
body>
html>
 
 
Demo
 
Downloads
 

The above code has been tested in the following browsers

Internet Explorer  FireFox  Chrome  Safari  Opera 

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