'By Greig Strachan 05/11/10
Option Explicit 'ensures all variables are declared
Dim intStart As Integer 'Start mileage
Dim intConsumed As Integer ' Fuel used
Dim intEnd As Integer 'End mileage
Dim strReg As String 'Registration number
Dim strManu As String 'Manufacturer
Dim strModel As String 'Car model
Dim intTotal As Integer 'Total amount of miles
Dim sngTotalFuel As Single 'total fuel consumed
Dim sngMpl As Single 'Fuel consumption in miles per litre


Private Sub cmdCalc_Click()

    'These if statements will make sure there is input
    If (txtCarReg.Text = "") Then
        MsgBox "Please enter a registration number", vbExclamation, "No input"
        Exit Sub
    End If

    If (txtStart.Text = "") Then
        MsgBox "Please enter a start mileage", vbExclamation, "No Input"
        Exit Sub
    End If

    If (txtEnd.Text = "") Then
        MsgBox "Please enter an end mileage", vbExclamation, "No Input"
        Exit Sub
    End If

    If (txtConsumed.Text = "") Then
        MsgBox "Please enter the amount of fuel used", vbExclamation, "No Input"
        Exit Sub
    End If

        intStart = txtStart.Text
        intEnd = txtEnd.Text

        intTotal = intEnd - intStart 'Calculation for total mileage

        txtTotal.Text = intTotal
        intConsumed = txtConsumed.Text

        sngMpl = intTotal / intConsumed 'Calculation for total fuel used

        txtTotalFuel = sngMpl

End Sub


Private Sub cmdReset_Click()

    txtStart.Text = ""
    txtEnd.Text = ""
    txtTotal.Text = ""
    txtCarReg.Text = ""
    txtManu.Text = ""
    txtModel.Text = ""
    txtTotalFuel = ""
    txtConsumed = ""

End Sub