ASP.NET自带的验证控件具有使用方便，开发快捷等优点。开发人员不必使用js就可以方便地对页面各项控件进行输入验证。但是它也有些不足之处，如：界面单调， 只能通过红色字体显示（当然自定义验证控件除外）；只能放在某一固定位置；需要占用一定的版面空间，如果错误消息比较长，会严重影响布局，即使将显示方式设为dynamic，当它显示错误消息时会撑大页面，影响美观，因此，我们有必要对它稍改进一下。
<%...@ Page Language="C#" AutoEventWireup="true" CodeBehind="myvalid.aspx.cs" Inherits="Test.myvalid" %>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>无标题页</title>
<style>...
.MsgC
{...}{
border-top:solid 1px #C6C3C6;
height:6px;
background-color:#FFFBEF;
font-size:1px;
}
.MsgL
{...}{
BACKGROUND: url(images/vMsgL.gif) no-repeat left top;
width:7px;
height:6px;
}
.MsgR
{...}{
BACKGROUND: url(images/vMsgR.gif) no-repeat ;
width:24px;
height:6px;
}
.MsgBL
{...}{
BACKGROUND: url(images/vMsgBL.gif) no-repeat left top;
width:7px;
height:6px;
}
.MsgBC
{...}{
BACKGROUND: url(images/vMsgBC.gif) repeat-x;
height:19px;
}
.MsgBR
{...}{
BACKGROUND: url(images/vMsgBR.gif) no-repeat left top;
width:24px;
height:19px;
}
</style>
</head>
<body style="font-size:12px">
<form id="form1" runat="server">
<div style="font-weight:bold;height:60px"> 打造自己的验证控件：</div>
姓名：<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" Display="dynamic" ControlToValidate="TextBox1"
ErrorMessage="请输入姓名！" SetFocusOnError="True"></asp:RequiredFieldValidator><br />
证件号：<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" Display="dynamic" ControlToValidate="TextBox2"
ErrorMessage="请输入证件号!" SetFocusOnError="True"></asp:RequiredFieldValidator>
<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" Display="dynamic" ControlToValidate="TextBox2"
ErrorMessage="证件号格式不符！" ValidationExpression="d{17}[d|X]|d{15}"></asp:RegularExpressionValidator><br />
<asp:Button ID="Button1" runat="server" Text="确定" />
</form>
</body>
</html>
<script type="text/javascript">...
function ValidatorUpdateDisplay(val) ...{
if (typeof(val.display) == "string") ...{
if (val.display == "None") ...{
return;
}
if (val.display == "Dynamic") ...{
//val.style.display = val.isvalid ? "none" : "inline";
// return;
}
}
if ((navigator.userAgent.indexOf("Mac") > -1) &&
(navigator.userAgent.indexOf("MSIE") > -1)) ...{
val.style.display = "inline";
}
ShowZfValidMsg(val);
// val.style.visibility = val.isvalid ? "hidden" : "visible";
}
function Page_ClientValidate(validationGroup) ...{
Page_InvalidControlToBeFocused = null;
if (typeof(Page_Validators) == "undefined") ...{
return true;
}
var i;
for (i = 0; i < Page_Validators.length; i++) ...{
ValidatorValidate(Page_Validators[i], validationGroup, null);
//Added By zhaofeng
if(!Page_Validators[i].isvalid)// only show one errmsg
...{
Page_IsValid = false;
Page_BlockSubmit = !Page_IsValid;
return false;
}
//Added End
}
ValidatorUpdateIsValid();
ValidationSummaryOnSubmit(validationGroup);
Page_BlockSubmit = !Page_IsValid;
return Page_IsValid;
}
function ShowZfValidMsg(val)
...{
//window.status = val.isvalid;
var tbId = "tbValidMsg";//+val.controltovalidate;
var tb = document.getElementById(tbId);
if(val.isvalid && tb == null) return;
我们研究一下ASP.NET的js代码(下载页面中WebResource.axd?d=SD1NUwMQGhYXe3jLq5kyhRg80avbG6v4rFgfT8pf7Lg1&t=633409665581718750指向的文件）发现用来显示错误消息的是ValidatorUpdateDisplay这个函数来完成的，关键的一句，是 val.style.visibility = val.isvalid ? "hidden" : "visible"; 如果我们想用alert方式显示的话，只需将这句改成alert(val.innerHTML)就可以了，但我们想做得更好看一点，做成类似于QQ聊天窗口的效果，效果可看下图：
要实现这个效果，需要以下几个图片。
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以下是源码：
<%...@ Page Language="C#" AutoEventWireup="true" CodeBehind="myvalid.aspx.cs" Inherits="Test.myvalid" %> <html xmlns="http://www.w3.org/1999/xhtml" ><head runat="server"> <title>无标题页</title><style>....MsgC{...}{ border-top:solid 1px #C6C3C6; height:6px; background-color:#FFFBEF; font-size:1px;}.MsgL{...}{ BACKGROUND: url(images/vMsgL.gif) no-repeat left top; width:7px; height:6px; }.MsgR{...}{ BACKGROUND: url(images/vMsgR.gif) no-repeat ; width:24px; height:6px;}.MsgBL{...}{ BACKGROUND: url(images/vMsgBL.gif) no-repeat left top; width:7px; height:6px; }.MsgBC{...}{ BACKGROUND: url(images/vMsgBC.gif) repeat-x; height:19px; }.MsgBR{...}{ BACKGROUND: url(images/vMsgBR.gif) no-repeat left top; width:24px; height:19px; }</style></head><body style="font-size:12px"> <form id="form1" runat="server"> <div style="font-weight:bold;height:60px"> 打造自己的验证控件：</div> 姓名：<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" Display="dynamic" ControlToValidate="TextBox1" ErrorMessage="请输入姓名！" SetFocusOnError="True"></asp:RequiredFieldValidator><br /> 证件号：<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox> <asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" Display="dynamic" ControlToValidate="TextBox2" ErrorMessage="请输入证件号!" SetFocusOnError="True"></asp:RequiredFieldValidator> <asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" Display="dynamic" ControlToValidate="TextBox2" ErrorMessage="证件号格式不符！" ValidationExpression="d{17}[d|X]|d{15}"></asp:RegularExpressionValidator><br /> <asp:Button ID="Button1" runat="server" Text="确定" /> </form></body></html><script type="text/javascript">... function ValidatorUpdateDisplay(val) ...{ if (typeof(val.display) == "string") ...{ if (val.display == "None") ...{ return; } if (val.display == "Dynamic") ...{ //val.style.display = val.isvalid ? "none" : "inline"; // return; } } if ((navigator.userAgent.indexOf("Mac") > -1) && (navigator.userAgent.indexOf("MSIE") > -1)) ...{ val.style.display = "inline"; } ShowZfValidMsg(val); // val.style.visibility = val.isvalid ? "hidden" : "visible";}function Page_ClientValidate(validationGroup) ...{ Page_InvalidControlToBeFocused = null; if (typeof(Page_Validators) == "undefined") ...{ return true; } var i; for (i = 0; i < Page_Validators.length; i++) ...{ ValidatorValidate(Page_Validators[i], validationGroup, null); //Added By zhaofeng if(!Page_Validators[i].isvalid)// only show one errmsg ...{ Page_IsValid = false; Page_BlockSubmit = !Page_IsValid; return false; } //Added End } ValidatorUpdateIsValid(); ValidationSummaryOnSubmit(validationGroup); Page_BlockSubmit = !Page_IsValid; return Page_IsValid;}function ShowZfValidMsg(val)...{ //window.status = val.isvalid; var tbId = "tbValidMsg";//+val.controltovalidate; var tb = document.getElementById(tbId); if(val.isvalid && tb == null) return;