While doing registration how
we will know that a particular name is available to the user.
Program
Default.aspx
code
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Untitled
Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
</div>
<asp:Button ID="Button1" runat="server" Text="Availability of
name from the database"
BackColor="#FF99FF" Font-Bold="True" Width="329px" /><br />
<asp:Label ID="Labelcheck"
Text="Please enter any
name to be verified from the database" runat="server" BackColor="#FFFF99"
Width="197px" ForeColor="#FF3300"></asp:Label>
<asp:TextBox ID="txtUserName" runat="server" Width="197px"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server"
ControlToValidate="txtUserName" ErrorMessage="*Name
Required"></asp:RequiredFieldValidator>
<br />
<asp:Label ID="lblMessage" runat="server" BackColor="#FF3300"
ForeColor="Black"></asp:Label>
</form>
</body>
</html>
Default.aspx.vb
code
Imports
System.Data.SqlClient
Imports
System.Data
Partial Class _Default
Inherits System.Web.UI.Page
Dim strConnString As String =
System.Configuration.ConfigurationManager.ConnectionStrings.Item("ConnectionString").ToString()
Dim
sqlda As SqlDataAdapter
Dim com As
SqlCommand
Dim ds As
DataSet
Dim str As String
Dim count As Integer
Protected Sub
Button1_Click(ByVal sender
As Object,
ByVal e As
System.EventArgs) Handles Button1.Click
namecheck()
End Sub
Sub namecheck()
Dim con As New SqlConnection(strConnString)
con.Open()
str =
"select count(*)from employee where ename='"
& txtUserName.Text & "'"
com =
New SqlCommand(str, con)
count =
Convert.ToInt32(com.ExecuteScalar)
If count > 0 Then
lblMessage.Text = "Sorry! you can't take this
username"
Else
lblMessage.Text = "You can take this username"
End If
End Sub
End Class
Output
Thanks for reading