Visual Basic If..Then..Else String statement - vb.net

Question

My friend and I are working on a simple program for class that allows you to determine the payroll depending on if the string is set to Processing or Sales. We want it to determine that when you place Sales in a text box, it will calculate that with the hours you input. Sales is multiplied by 20.
This is what we have at the moment.
Private Sub calcButton_Click(sender As Object, e As EventArgs) Handles calcButton.Click
'declare
Dim total As Double
Dim weekly As Double
Dim weekly1 As Double
Dim weekly2 As Double
Dim weekly3 As Double
Dim weekly4 As Double
Dim hours1 As Double
Dim hours2 As Double
Dim hours3 As Double
Dim hours4 As Double
Dim dep1 As Integer
Dim dep2 As Integer
Dim dep3 As Integer
Dim dep4 As Integer
Double.TryParse(hoursWorked1TB.Text, hours1)
Double.TryParse(hoursworked2TB.Text, hours2)
Double.TryParse(hoursWorked3TB.Text, hours3)
Double.TryParse(hoursWorked4TB.Text, hours4)
'as decimal
weeklyPay1.Text = weekly.ToString("C1")
weeklyPay2.Text = weekly.ToString("C1")
weeklyPay3.Text = weekly.ToString("C1")
weeklyPay4.Text = weekly.ToString("C1")
'sales and processing
If dep1TB.Text = "Sales" Then
dep1 = 20
ElseIf dep1TB.Text = "Processing" Then
dep2 = 15
Else : dep1 = 0
End If
If dep2TB.Text = "Sales" Then
dep2 = 20
ElseIf dep2TB.Text = "Processing" Then
dep2 = 15
Else : dep2 = 0
End If
If dep3TB.Text = "Sales" Then
dep3 = 20
ElseIf dep3TB.Text = "Processing" Then
dep3 = 15
Else : dep3 = 0
End If
If dep4TB.Text = "Sales" Then
dep4 = 20
ElseIf dep4TB.Text = "Processing" Then
dep2 = 15
Else : dep4 = 0
End If
'calculations
weekly1 = hours1 * dep1
weekly2 = hours2 * dep2
weekly3 = hours3 * dep3
weekly4 = hours4 * dep4
total = weekly1 + weekly2 + weekly3 + weekly4
End Sub
Later I determined that we need an As String variable, but everything still returns as 0.

Answer 1

I assume your code that the following commented lines are typos:
If dep1TB.Text = "Sales" Then
dep1 = 20
ElseIf dep1TB.Text = "Processing" Then
dep2 = 15 ' should `dep1` instead?
Else : dep1 = 0
End If
And here:
If dep4TB.Text = "Sales" Then
dep4 = 20
ElseIf dep4TB.Text = "Processing" Then
dep2 = 15 ' should `dep4` instead?
Else : dep4 = 0
End If
If so, you could rewrite your code like this:
Private Sub calcButton_Click(sender As Object, e As EventArgs)
Dim total As Double
Dim hoursWorkedTBs() As TextBox = { hoursWorked1TB, hoursWorked2TB, hoursWorked3TB, hoursWorked4TB }
Dim weeklyPayTBs() As TextBox = { weeklyPay1, weeklyPay2, weeklyPay3, weeklyPay4 }
Dim depTBs() As TextBox = { dep1TB, dep2TB, dep3TB, dep4TB }
Dim weekly(4) As Double
Dim hours(4) As Double
Dim dep(4) As Integer
For i = 0 to 3
hours(i) = double.Parse(hoursWorkedTBs(i).Text)
If depTBs(i).Text = "Sales" Then
dep(i) = 20
ElseIf depTBs(i).Text = "Processing" Then
dep(i) = 15
Else
dep(i) = 0
End If
weekly(i) = hours(i) * dep(i)
weeklyPayTBs(i).Text = weekly(i).ToString("C1")
Next
total = weekly.Sum()
End Sub
Notice that the weekly pay text boxes are updated after the calculations are performed. In the most part, that's where your code went wrong.