Mortgage Calculator

Public Class Form1
Private Loan_amount, Loan, Rate, Payment, i As Double
Private Years, Month As Integer

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Loan_amount = Double.Parse(TextBox1.Text)
Rate = Double.Parse(TextBox2.Text) / 100 / 12
Years = Integer.Parse(TextBox3.Text * 12)
Payment = Loan_amount * Rate / (1 - 1 / (Math.Pow(1 + Rate, Years)))
listbox1.Items.Add(String.Format("{0, 10:C2}", Payment))

End Sub
Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles listbox1.SelectedIndexChanged
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
'Dim i As Double
Loan = Double.Parse(TextBox1.Text)
Rate = Double.Parse(TextBox2.Text)
Years = Integer.Parse(TextBox3.Text) * 12
listbox1.Items.Add(String.Format("{0,-20} {1,20}", "Interest", "Payment"))
For i As Double = 5 To 14 Step 0.5
Rate = i / 12 / 100
Payment = Loan_amount * Rate / (1 - 1 / (Math.Pow(1 + Rate, Years)))
listbox1.Items.Add(String.Format("{0,-20:N1} {1,20:C2}", i, Payment))
Next
End Sub
End Class

String Manipulation

Public Class Form1
Dim myurl As String = "http://www.google.com"
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Label1.Text = myurl.IndexOf(":")
Label2.Text = Mid(myurl, 1, 4)
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Label3.Text = myurl.IndexOf("//")
Label4.Text = Mid(myurl, myurl.IndexOf("//") + 3, myurl.IndexOf(".") - myurl.IndexOf("//") - 2)
Label5.Text = Mid(myurl, myurl.IndexOf("//") + 3, myurl.IndexOf(".") - myurl.IndexOf("//") - 0)
End Sub
End Class

Class and Object

Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'Create instance of class
Dim mycar As New Car()
'Using properties
mycar.Make = "Subaru"
mycar.Model = "Outback"
mycar.ElapsedMileage = "59000"
'Calling properties
MessageBox.Show(mycar.Make)
MessageBox.Show(mycar.ElapsedMileage)
'Calling a method
MessageBox.Show(mycar.Drive(250))
'Create instance of class using Inherits
Dim mytruck As New truck()
'Using properties of new class
mytruck.Make = "Mazda"
mytruck.Model = "B4000"
mytruck.ElapsedMileage = "40000"
'Calling properties of new class
MessageBox.Show(mytruck.Make)
MessageBox.Show(mytruck.ElapsedMileage)
'Calling a method of new class
MessageBox.Show(mytruck.Drive(250))
End Sub
End Class

I added a new item (class) so it had its own page (tab)

Public Class Car
' Fields
Private m_make As String
Private m_model As String
Private m_elapsedMileage As String

'Properties
Public Property Make()
Get
Return m_make
End Get
Set(ByVal value)
m_make = value
End Set
End Property
Public Property Model()
Get
Return m_model
End Get
Set(ByVal value)
m_model = value
End Set
End Property
Public Property ElapsedMileage()
Get
Return m_elapsedMileage
End Get
Set(ByVal value)
m_elapsedMileage = value
End Set
End Property

' Method
Public Function Drive(ByVal miles As Integer) As String
m_elapsedMileage += miles
Dim result As String
result = "The " & m_make & " " & m_model & " now has " & m_elapsedMileage & " miles after the trip."
Return result
End Function
End Class

Public Class truck
Inherits Car
End Class