Answer:
Introduction:
In this application, we use database concept to check if the username and password are correct or not. If username and password get matched, then user gets redirected to the home page otherwise to the login page.
Steps to develop the login page.
1. Create a table “UserLogIn”, with two columns such as username and password.
create table UserLogin (username varchar(20), password varchar(20))
2. Create a Stored procedure “Validate-User” to check if the username and password match or not.
CREATE PROCEDURE [dbo].[Validate_User]
@Username VARCHAR(20),
@Password VARCHAR(20),
@Msg varchar(200) out
AS
set @Msg = ''
SET NOCOUNT ON
IF EXISTS(SELECT * FROM UserLogIn WHERE username = @username AND password = @password)
set @Msg = 'Valid password'
ELSE
set @Msg = 'Invalid username or password'
3. Develop the web page in VB.NET
Login.aspx
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>LogIn Page</title>
</head>
<body>
<%@ Import Namespace="System.Data.SqlClient" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System" %>
<%@ Import Namespace=" System.Configuration" %>
<script language="VB" runat="server">
Protected Sub ValidateUser(sender As Object, e As EventArgs)
Using oConn As New SqlConnection
Dim cmd As New SqlCommand
Dim pIn As New SqlParameter
Dim pOut As New SqlParameter
oConn.ConnectionString = ConfigurationSettings.AppSettings("ConnectionString")
oConn.Open()
cmd = New SqlCommand("Validate_User", oConn)
cmd.CommandType = CommandType.StoredProcedure
pIn = cmd.Parameters.Add("@Username", SqlDbType.VarChar, 20)
pIn.Value = txtUserid.Text
pIn = cmd.Parameters.Add("@Password", SqlDbType.VarChar, 20)
pIn.Value = txtPwd.Text
Dim Msg As New SqlParameter("@Msg", SqlDbType.VarChar, 200)
Msg.Direction = ParameterDirection.Output
cmd.Parameters.Add(Msg)
cmd.ExecuteNonQuery()
lblStatus.Visible = True
lblStatus.Enabled = True
lblStatus.Text = Msg.Value
If Msg.Value = "Valid password" Then
Response.Redirect("welcome.aspx")
End If
End Using
End Sub
</script>
<body>
<form id="form1" runat="server">
<fieldset style="width:280px; background-color:aqua">
<asp:Label ID="lblStatus" runat="server" Text=""></asp:Label>
<table>
<tr>
<td>User ID:<font color="#cc0000">*</font></td>
<td><asp:TextBox ID="txtUserid" runat="server"></asp:TextBox><br /></td>
</tr>
<tr>
<td> Password:<font color="#cc0000">*</font></td>
<td><asp:TextBox ID="txtPwd" runat="server" TextMode="Password"></asp:TextBox><br /></td>
</tr>
<tr>
<td></td>
<td><asp:Button ID="btnLogin" runat="server" Text="Login" OnClick ="ValidateUser" /></td>
</tr>
</table>
</fieldset>
</form>
</body>
</html>
Output:
1. Username or password are not matched
2. Username and password are matched
