bu neden hata yapıo sadece 2. girilen değeri alıp işlem yapıo neden ??



Private Sub Command1_Click(Index As Integer)
Text1.Text = Text1.Text & 0
End Sub

Private Sub Command10_Click()
Text1.Text = Text1.Text & 9
End Sub

Private Sub Command11_Click()
a = Text1.Text
Label1.Caption = "+"
Text1.Text = ""
Text1.SetFocus
End Sub

Private Sub Command12_Click()
a = Text1.Text
Label1.Caption = "-"
Text1.Text = ""
Text1.SetFocus
End Sub


Private Sub Command13_Click()
a = Text1.Text
Label1.Caption = "÷"
Text1.Text = ""
Text1.SetFocus
End Sub

Private Sub Command14_Click()
a = Text1.Text
Label1.Caption = "x"
Text1.Text = ""
Text1.SetFocus
End Sub

Private Sub Command15_Click()
b = Text1.Text
If (Label1.Caption = "+") Then
Label2 = Val(a) + Val(b)
Else
If (Label1.Caption = "-") Then
Label2 = Val(a) - Val(b)
Else
If (Label1.Caption = "÷") Then
Label2 = Val(a) / Val(b)
Else
If (Label1.Caption = "x") Then
Label2 = Val(a) * Val(b)
End If
End If
End If
End If
End Sub

Private Sub Command16_Click()
Text1.Text = Text1.Text & "."
End Sub

Private Sub Command17_Click()
Text1.Text = " "
Label1.Caption = " "
Text1.SetFocus

End Sub


Private Sub Command2_Click()
Text1.Text = Text1.Text & 1
End Sub

Private Sub Command3_Click()
Text1.Text = Text1.Text & 2
End Sub

Private Sub Command4_Click()
Text1.Text = Text1.Text & 3
End Sub

Private Sub Command5_Click()
Text1.Text = Text1.Text & 4
End Sub

Private Sub Command6_Click()
Text1.Text = Text1.Text & 5
End Sub

Private Sub Command7_Click()
Text1.Text = Text1.Text & 6
End Sub

Private Sub Command8_Click()
Text1.Text = Text1.Text & 7
End Sub

Private Sub Command9_Click()
Text1.Text = Text1.Text & 8
End Sub
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