username & password validation

Question

User1667772157 posted

I am trying to validate a username and password that has been entered in a text box, and validating it against a username and password that is in an Access database.  How would I do that in visual web developer using sql?

Answer 1

User-874886737 posted

In the onclick of the logon button, try something like (I'm using VB.NET):

       Dim strConn As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=|DataDirectory|userdatabase.mdb"
        Dim cn As New OleDbConnection(strConn)
        Try
            cn.Open()
            Dim cm As New OleDbCommand("SELECT COUNT(*) FROM users WHERE username=? AND password=?;", cn)
            cm.Parameters.AddWithValue("?",TextBoxUsername.Text)
            cm.Parameters.AddWithValue("?",TextBoxPassword.Text)
            Dim count As Integer = CInt(cm.ExecuteScalar())
            If(count>0) Then
                  ' user successfully logged on
                  ' do something
            Else
                 lblError.Text = "Logon failed"
            End If
        Catch ex As Exception
            lblError.Text = ex.Message()
        Finally
            cn.Close()
        End Try

Jos

Answer 2

User-855621155 posted
can you give the same exemple in c# code?

Answer 3

User-874886737 posted

Automatic translation from vb to C#:

http://labs.developerfusion.co.uk/convert/vb-to-csharp.aspx

Jos

Answer 4

User-298397817 posted

create procedure CheckLoginDetails

(

@username  nvarchar(100),

@password nvarchar(100)

)

As

Begin

 

select Count(*) from tablename where Username=@username ,password=@password

 

 

End

 

 

in Codebehind Ur using Executescalar.

Answer 5

User984479729 posted

con.Open();
        SqlCommand cmd = new SqlCommand("select count(username) from newuser where username='" + txt_uname.Text + "' and password='" + txt_pwd.Text + "'", con);
        String str1 = Convert.ToString(cmd.ExecuteScalar());
        con.Close();
        if (str1 =="1")
        {
            Response.Redirect("home.aspx");
        }
        else
        {
            Response.Write("Please be a member");
        }

Answer 6

User-1199946673 posted

Very cool, but you obviously never heard of SQL injections?

http://www.mikesdotnetting.com/Article/113/Preventing-SQL-Injection-in-ASP.NET

Also, password is a Reserved word in Jet, so when using this as a fieldname, it should be enclosed in brackets...

[password]

A simple login system using Access can be found here:

http://www.mikesdotnetting.com/Article/75/Simple-Login-and-Redirect-for-ASP.NET-and-Access

But why not use the Membership provider?

http://imar.spaanjaars.com/404/using-the-microsoft-access-providers-to-replace-the-built-in-sql-server-providers
http://imar.spaanjaars.com/560/using-the-microsoft-access-providers-for-membership-roles-and-profile-under-aspnet-4