Answer of your question is very broad. So instead of code i am giving you the algorithm.
1. Create a method that will check the supplied user name and password in your data layer file.
E.g. bool IsAuthenticatedUser(). Inside this method run Command.ExecuteScalar. Here is query "
Declare @Count =(Select Count(*) From Login
Where UserName = @UserNAme and Password = @Password)
Select @Count;
-- Assuming u r using Sql Server 2008
2. Now in your IsAuthenticated Method check if the returned value is one then return true else false. Something like this
int count = (int)command.ExecuteScalar();
If (count ==1)
{
return true;
}
return false;
3. On the UI check the value returned by the method. If its true redirect the user to its page. And set session. For displaying name email id on page,
After the success of IsAuthenticated method, Create another method that will select your desired entities from database and fill it in datatable.
Something like this
If(IsAuthenticatedUser(username, password))
{
Datatable dt = GetUserDetails(username,password);
If(dt!=null)
{
if(dt.rows.count >0)
{
// here there is only one row so you can use index [0] also
foreach(DataRow dr in dt.rows)
{
Session["UserName"] = dr["UserName"].tostring();
Session["Email"] = dr["Email"].tostring();
}
}
}
Now on the desired page check if the both sessions are not null , then set the value at desired label.
If (Session["UserName"]!=null && Session["Email"]!=null)
{
lblUserName.Text = "Welcome " + Session["UserName"].ToString();
lblEmail.Text = Session["Email"].tostring();
}
**Here userName and password parameter will be the value passed from the textbox.
string username = txtUserName.text.trim();
string password = txtPassword.text.trim();
Also you to put validations before accepting input from users, as this may result in sql injection and exposing of your entire database. but for home purpose you can do this.**
See Update:
For displaying name on every page Create a master page and add the two labels on that. For adding master page , from context menu Add New Item -> MasterPage. Now in source view add table as per your need. Also there is ContentPlaceholder , do not add inside that tag. That is the space to display the other child pages. in the master page load event use the label = session code to set the name. Also there add a link button , in its click event use
Session.Abandon();
Response.Redirect("~/Login.aspx?Logout=1");
-> i have added a new thing ?Logout called query string , used for passing values from one page to another. Here i am using Login =1 that means I can know ia m on login page because i logged out myself.
