<%@ Page Language="C#" AutoEventWireup="True" %>
<Script language="C#" runat="server">
void Page_Load(Object Sender,EventArgs e){
}
void ButtonClick(Object Sender,EventArgs E){
if (Page.IsValid){
Label_1.Text=TextBox_1.Text;
}
else{
Label_1.Text="Error input!";
}
}
</Script>
<form id="Form_1" runat="server">
<asp:textbox ID="TextBox_1" runat="server"/>
<asp:RegularExpressionValidator id="RegularExpressionValidator1"
ControlToValidate="TextBox_1"
ValidationExpression=".*@.*..*"
Display="Static"
EnableClientScript="false"
ErrorMessage="Error E-mail!"
runat="server"/>
<asp:button ID="Button_1" Text="Button" OnClick="ButtonClick" runat="server"/>
</form>
<asp:label ID="Label_1" runat="server"></asp:label>