Calculator program using visual basic

I got an assignment from college and I need to create calculating application using visual basic. I am very poor in a programming so some one help me to write program in visual basic. I can create user interface only but can not write code for each button so help me write program.

Code:

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Private Operator  As String
Private First As String


Private Sub cmdClear_Click()
    First = ""
    Operator = ""
End Sub

Private Sub cmdEquals_Click()
Select Case Operator
    Case Is = "+"
        Text1.Text = First + Text1.Text
    Case Is = "-"
        Text1.Text = First - Text1.Text
    Case Is = "/"
        Text1.Text = First / Text1.Text
    Case Is = "*"
        Text1.Text = First * Text1.Text
End Select
    First = ""
    Operator = ""
End Sub

Private Sub cmdOperator_Click(Index As Integer)
    Operator = cmdOperator(Index).Caption
    First = Text1.Text
    Text1.Text = ""
End Sub

Private Sub Command1_Click(Index As Integer)
    Text1.Text = Text1.Text + Command1(Index).Caption
End Sub

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This program will help you.

Code:

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Private LastOpe  As String
Private num As String
Private Sub Form_Load()
    txtResult.Enabled = False
    Me.KeyPreview = True
End Sub

Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
    ' numbers in main keyboard
    If (KeyCode >= 48 And KeyCode <= 57) Then
        AddDigits (Chr(KeyCode))
    End If
 
    ' numbers in numpad
    If (KeyCode >= 96 And KeyCode <= 105) Then
        AddDigits (Chr(KeyCode - 48))
    End If
 
    'if backspace
    If (KeyCode = 8) Then
        If (txtResult.Text <> "") Then
        txtResult.Text = Left(txtResult.Text, Len(txtResult.Text) - 1)
        End If
    End If
    'for various operators
    If (KeyCode = 111) Then RegisterOperator ("/")
    If (KeyCode = 106) Then RegisterOperator ("*")
    If (KeyCode = 109) Then RegisterOperator ("-")
    If (KeyCode = 107) Then RegisterOperator ("+")
End Sub
Private Sub cmdOperator_Click(Index As Integer)
    RegisterOperator (cmdOperator(Index).Caption)
End Sub
Private Sub cmdClear_Click()
  num = ""
    LastOpe = ""
    txtResult.Text = ""
 
End Sub
Private Sub cmdEquals_Click()
    Select Case LastOpe
        Case Is = "+"
            txtResult.Text = num+ txtResult.Text
        Case Is = "-"
            txtResult.Text = num - txtResult.Text
        Case Is = "/"
            txtResult.Text = num / txtResult.Text
        Case Is = "*"
            txtResult.Text =num * txtResult.Text
    End Select
        num = ""
        LastOpe = ""
End Sub
Private Sub Command1_Click(Index As Integer)
    AddDigits (Command1(Index).Caption)
End Sub
 
Private Sub AddDigits(Digit As String)
    txtResult.Text = txtResult.Text & Digit
End Sub
Private Sub RegisterOperator(OperatorText As String)
    LastOpe = OperatorText
    num = txtResult.Text
    txtResult.Text = ""
End Sub

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Code:

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  Dim first As Double
  Dim second As Double
  Dim opr As String


Private Sub Command1_Click(Index As Integer)
        If txtView.Text = "" Then
          txtView.Text = Command1(Index).Caption
        Else
            txtView.Text = txtView.Text & Command1(Index).Caption
        End If
  End Sub


Private Sub Command2_Click(Index As Integer)
        first = txtView.Text
        txtView.Text = ""
        opr= Command2(Index).Caption
  End Sub

Private Sub Form_Load()
  txtView.Enabled = False
  txtView.MaxLength = 10
  End Sub

Private Sub cmdEq_Click()
        second = txtView.Text
      If opr= "-" Then
            txtView.Text = first - second
        ElseIf opr = "+" Then
            txtView.Text = first + second
        ElseIf opr = "*" Then
            txtView.Text  = first * second
        ElseIf opr = "/" Then
            txtView.Text = first / second
        End If
  End Sub


Private Sub cmdDot_Click()
        If InStr(txtView.Text, ".") = 0 Then
            txtView.Text = txtView.Text & "."
        End If
  End Sub

Private Sub cmdClear_Click()
      txtView.Text = "0"
  End Sub

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