<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<%@ Register assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" tagprefix="ajaxToolkit" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:Label ID="Label1" runat="server" Text="标題："></asp:Label>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<ajaxToolkit:TextBoxWatermarkExtender ID="TextBox1_TextBoxWatermarkExtender" runat="server" TargetControlID="TextBox1" WatermarkText="請輸入标題" WatermarkCssClass="watermark"/>
<br />
<asp:Label ID="Label2" runat="server" Text="備注："></asp:Label>
<asp:TextBox ID="TextBox2" runat="server" BorderColor="#DAEEEE" CssClass="txt" Height="70px" TextMode="MultiLine" Width="148px"></asp:TextBox>
<ajaxToolkit:TextBoxWatermarkExtender ID="TextBox2_TextBoxWatermarkExtender" runat="server" TargetControlID="TextBox2" WatermarkText="請輸入備注" WatermarkCssClass="watermark" />
<br />
</div>
</form>
</body>
</html> 
轉載于:https://www.cnblogs.com/luxiaoyao/p/6184455.html