SQLCommand.Parameters.AddWithValue("@varAlias", Trim(txAlias.Text))
SQLCommand.Parameters.AddWithValue("@varPass", Trim(txPassword.Text))

'Import some important things including the database 'wrapper'
Imports Rain.fSQL, System, System.Security.Cryptography, System.Text
 
Public Class Login
 
    Dim tmpSuccess As Boolean = False
    Dim tmpNoOfTries As Integer
    Private Function Login() As Object
        If txAlias.Text = "" Or txPassword.Text = "" Then
            MsgBox("You left a required field empty!", MsgBoxStyle.Exclamation)
        Else
            'Create the SQL string
            Dim sqlCheckData As String = "SELECT * FROM tUsers WHERE uAlias = @varAlias AND uPass = @varPass"
            'Encode the password
            'Add the username and password into the sql string
            SQLCommand.Parameters.AddWithValue("@varAlias", Trim(txAlias.Text))
            SQLCommand.Parameters.AddWithValue("@varPass", Trim(txPassword.Text))
            'Create the SQL connection
            fSQL.SQLConnectionCreate()
            SqlCommand.Connection = SqlConnection
            'Add the SQL
            SqlCommand.CommandText = sqlCheckData
            'Execute the query
            SqlCommand.ExecuteNonQuery()
            'Create a data reader
            SQLData = SqlCommand.ExecuteReader
            'If any data is found then the username exists
            If SQLData.Read() Then
                tmpSuccess = True
            Else
                tmpSuccess = False
            End If
            fSQL.SQLConnectionClose()
        End If
        Return tmpSuccess
    End Function
 
    Private Sub btClose_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btClose.Click
        Me.Close()
    End Sub
 
    Private Sub btLogin_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btLogin.Click
        Login()
        If tmpSuccess = True Then
            btLogin.Enabled = False
            MainApp.Show()
            Me.Close()
        End If
        If tmpSuccess = False Then
            tmpNoOfTries += 1
            MsgBox("Logging in failed, please try again. You have had " & tmpNoOfTries & " of 5 goes", MsgBoxStyle.Exclamation)
        End If
        If tmpNoOfTries >= 5 Then
            btLogin.Enabled = False
            lbWarning.Text = "Too many failed attempts!"
        End If
    End Sub
End Class

Imports System.Data, System.Data.SqlClient
Module fSQL
    'SQL connection variables
    Public SQLConnection As New SqlConnection()
    Public SQLCommand As New SqlCommand()
    Public SQLData As SqlDataReader
    'SQL connection functions
    'Function used for creating the database connection
    Public Function SQLConnectionCreate() As Object
        If SQLConnection.State = ConnectionState.Closed Then
            'Create the Connection String
            Dim SQLConnectionString As String = "Data Source=LAMBDA\SQLEXPRESS;Initial Catalog=Rain;User ID=Skyrail;Password=*******"
            'Set the connection string into the SQL connection
            SQLConnection.ConnectionString = SQLConnectionString
            'Open up the connection
            SQLConnection.Open()
        End If
        'Return the connection status
        Return SQLConnection
    End Function
    'Function used for closing the database connection
    Public Function SQLConnectionClose() As Object
        If SQLConnection.State = ConnectionState.Open Then
            'Close the connection
            SQLConnection.Close()
        End If
        Return SQLConnection
    End Function
End Module

Private Function ExecuteQuery(ByVal cmd As SqlCommand) As DataSet
        Dim dbConnection As New SqlConnection(connectionString)
 
        cmd.Connection = dbConnection
 
        Dim dbAdapter As New SqlDataAdapter()
        dbAdapter.SelectCommand = cmd
 
        Dim resultSet As New DataSet()
 
        dbConnection.Open()
        Try
            dbAdapter.Fill(resultSet)
        Finally
            dbConnection.Close()
        End Try
 
        Return resultSet
    End Function

Dim cmd As New SqlCommand()
cmd.CommandType = CommandType.Text
cmd.CommandText = "SELECT column_name FROM table_name WHERE column_name = @inputParam;"
 
cmd.Parameters.AddWithValue("@inputParam", value)
 
Dim results As New DataSet
results = ExecuteQuery(cmd)

 
Dim sqlCmd As New SqlCommand()
            sqlCmd.CommandType = CommandType.Text
            sqlCmd.CommandText = "SELECT * FROM tUsers WHERE uAlias = @varAlias AND uPass = @varPass;"
            sqlCmd.Parameters.AddWithValue("@varAlias", txAlias.Text)
            sqlCmd.Parameters.AddWithValue("@varPass", varPassword)
 
            Dim sqlCmdResults As New DataSet
            sqlCmdResults = sqlQuery(sqlCmd)

Public Function sqlQuery(ByVal dbSqlCommand As SqlCommand) As DataSet
 
        'Set the connection string
        Dim dbConnectionString As String = "Data Source=LAMBDA\SQLEXPRESS;Initial Catalog=Rain;User ID=Skyrail;Password=*****"
        'Create a database connection function
        Dim dbConnection As New SqlConnection(dbConnectionString)
        'Set up the database adapter
        Dim dbAdapter As New SqlDataAdapter()
        'Create a dataset to put data into
        Dim dbResultData As New DataSet()
 
        'Put the connection data into the function
        dbSqlCommand.Connection = dbConnection
        'Something to do with the adapter
        dbAdapter.SelectCommand = dbSqlCommand
        'Open the connection
        dbConnection.Open()
 
        'Try and put data into the adapter
        Try
            dbAdapter.Fill(dbResultData)
        Finally
            dbConnection.Close()
        End Try
 
        Return dbResultData
    End Function