vs网页aspx中前台代码

HTML代码中用户名不能为空代码如下:

<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="txtUserName" ErrorMessage="*用户名不能为空"></asp:RequiredFieldValidator>

HTML代码中密码是否一致判断代码如下:

<asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" ControlToValidate="txtPassword" ErrorMessage="*"></asp:RequiredFieldValidator>
<asp:CompareValidator ID="CompareValidator1" runat="server" ControlToCompare="txtPassword" ControlToValidate="txtPassword2" ErrorMessage="密码不一致"></asp:RequiredFieldValidator>

HTML代码中邮箱地址判断代码如下:

<asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server" ControlToValidate="txtEmail" ErrorMessage="*"></asp:RequiredFieldValidator>
<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="txtEmail" 
ErrorMessage="无效的邮箱地址" ValidationExpression="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*">
</asp:RegularExpressionValidator>