usersdb.vb

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Imports System
Imports System.Data
Imports System.Data.SqlClient
Imports System.Collections

Namespace IBuyAdventure

   Public Class UsersDB
   
      Dim m_ConnectionString As String

      Public Sub New(dsn As String)
         m_ConnectionString = dsn
      End Sub

      Public Sub AddNewUser(customerName As String, password As String)

          Dim insertStatement As String = "INSERT INTO Accounts (CustomerName, Password) values ('" _
          	& customerName & "', '" & password & "')"

          Dim sqlConnection As New SqlConnection(m_ConnectionString)
          Dim myCommand As New SqlCommand(insertStatement, sqlConnection)

          myCommand.Connection.Open()
          myCommand.ExecuteNonQuery()
          myCommand.Connection.Close()
          
      End Sub 
  
     Public function UserExists(customerName As String) As Boolean
     
          Dim sqlConnection As New SqlConnection(m_ConnectionString)
          Dim sqlAdapter1 As New SqlDataAdapter("SELECT CustomerName FROM Accounts WHERE CustomerName='" _
          	& customerName & "'", sqlConnection)

          Dim accountDetails As New DataSet()
          sqlAdapter1.Fill(accountDetails, "accountDetails")

          If accountDetails.Tables(0).Rows.Count < 1 Then
            Return False
	  Else
	    Return True
	  End If
	    
      End Function

      
      Public Function ValidateLogin(customerName As String, password As String) As Boolean
      
          Dim sqlConnection As New SqlConnection(m_ConnectionString)
          Dim sqlAdapter1 As New SqlDataAdapter("SELECT * FROM Accounts WHERE CustomerName='" _
          	& customerName & "'", sqlConnection)

          Dim accountDetails As New DataSet()
          sqlAdapter1.Fill(accountDetails, "accountDetails")

          If accountDetails.Tables(0).Rows.Count < 1 Then
            Return False
          End If
          
          return String.Compare(password.Trim(), accountDetails.Tables(0).Rows(0)("Password").Trim()) = 0
      End Function
      
   End Class

End Namespace