Solved

Login Control UserName Only Accept the Initial Test Value of UserName and Password, Can't Test Any other set

Posted on 2012-12-28
2
457 Views
Last Modified: 2012-12-30
Hi,

I am a beginner of .Net Web Developer.

I programmed a simple Web app in VB.NET 2005 to let an user log in at first, and the UserName will be passed to the next page for displaying his or her relevant information .

the Login Control connects to a data table in SQL Server 2005 for log in authentication. I used UserID stored in the database as value of UserName text field of the Login control.

The problem is, during my many tests, only the very first UserID and password (the password is actually an user's last name) got successfully log in, no matter how many time to repeat to use this set of value. Except this set of value, the Login process was never succeed when using any other pairs of UserID and LastName, even I ensured to type in correct value in the text fields.

Your advise will be very appreciate!

Part of my code: -----------------------------------------------------------------

Private Function YourValidationFunction(ByVal UserName As String, ByVal Password As String) As Boolean


        Dim boolReturnValue As Boolean = False
        Dim strConnection As String = "Data Source=myServerName;Initial Catalog=myDatabaseName;Integrated Security=True;"
        Dim sqlconnection As New SqlClient.SqlConnection(strConnection)
        Dim SQLQuery As String = "SELECT distinct [UserId],[Last name] FROM myUserTable"
        Dim command As New SqlClient.SqlCommand(SQLQuery, sqlconnection)
        Dim Dr As SqlClient.SqlDataReader
        sqlConnection.Open()
        Dr = command.ExecuteReader()
        While Dr.Read()
            If (UserName = Dr("UserID").ToString()) And (Password = Dr("Last name").ToString()) Then
                boolReturnValue = True
            End If
            Dr.Close()
            Return boolReturnValue
        End While
        Return boolReturnValue
    End Function
0
Comment
Question by:GaiaGia
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 
LVL 83

Accepted Solution

by:
CodeCruiser earned 500 total points
ID: 38728215
The problem is that you have return statement within your While loop which means that while loop only executes once.

I would change your code to below

Private Function YourValidationFunction(ByVal UserName As String, ByVal Password As String) As Boolean
        Dim boolReturnValue As Boolean = False
        Dim strConnection As String = "Data Source=myServerName;Initial Catalog=myDatabaseName;Integrated Security=True;"
        Dim sqlconnection As New SqlClient.SqlConnection(strConnection)
        Dim SQLQuery As String = "SELECT Count(UserID) FROM MyUserTable Where [UserId]=@UserID AND [Last name]=@LastName"
        Dim command As New SqlClient.SqlCommand(SQLQuery, sqlconnection)
        sqlConnection.Open()
        command.Parameters.AddWithValue("@UserID", UserName)
        command.Parameters.AddWithValue("@LastName", Password)
        Dim cnt As Integer = command.ExecuteScalar()
        If cnt = 1 Then
            boolReturnValue = True
        End If
        command.Dispose
        sqlConnection.Dispose
        Return boolReturnValue
    End Function

Open in new window

0
 

Author Closing Comment

by:GaiaGia
ID: 38730984
Thank you, CodeCruiser!
0

Featured Post

Increase Agility with Enabled Toolchains

Connect your existing build, deployment, management, monitoring, and collaboration platforms. From Puppet to Chef, HipChat to Slack, ServiceNow to JIRA, Splunk to New Relic and beyond, hand off data between systems to engage the right people.

Connect with xMatters.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction This article shows how to use the open source plupload control to upload multiple images. The images are resized on the client side before uploading and the upload is done in chunks. Background I had to provide a way for user…
Calculating holidays and working days is a function that is often needed yet it is not one found within the Framework. This article presents one approach to building a working-day calculator for use in .NET.
Come and listen to Percona CEO Peter Zaitsev discuss what’s new in Percona open source software, including Percona Server for MySQL (https://www.percona.com/software/mysql-database/percona-server) and MongoDB (https://www.percona.com/software/mongo-…
There's a multitude of different network monitoring solutions out there, and you're probably wondering what makes NetCrunch so special. It's completely agentless, but does let you create an agent, if you desire. It offers powerful scalability …

717 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question