degreez,

Private mypoint1 As Boolean, mypoint2 As Boolean
Private Sub MySub(KeyAscii As Integer, t As TextBox, mypoint As Boolean)
Select Case Chr(KeyAscii)
Case "+", "-"
If t.Text <> "" Then KeyAscii = 0
Case ","
If mypoint = False Then mypoint = True Else KeyAscii = 0
Case "0" To "9"
Case Else
KeyAscii = 0
End Select
End Sub

Private Sub txtA_KeyPress(KeyAscil As Integer)
Call MySub(KeyAscil, txtA, mypoint1)
End Sub
Private Sub txtB_KeyPress(KeyAscil As Integer)
Call MySub(KeyAscil, txtB, mypoint2)
End Sub
Private Sub txtA_Click()
txtA.Text = ""
mypoint1 = False
End Sub
Private Sub txtB_Click()
txtB.Text = ""
mypoint2 = False
End Sub
Private Sub cmdClear_Click()
txtA.Enabled = True
txtB.Enabled = True
txtA.Text = 0
txtB.Text = 0
lblZ.Caption = ""
Fraka1.Enabled = True
opt1.Value = True
mypoint1 = False
mypoint2 = False
txtA.SetFocus
End Sub

Private Sub cmdExit_Click()
End
End Sub

Private Sub cmdStart_Click()
Dim a As Single
Dim b As Single
On Error GoTo lbl
a = txtA.Text
b = txtB.Text
Select Case True
Case opt1.Value = True
z = a + b
Case opt2.Value = True
z = a - b
Case opt3.Value = True
z = a * b
Case opt4.Value = True
z = a / b
End Select
lblZ.Caption = z
lblZ.Caption = Format(z, "#0.0###")
'lblZ.AutoSize = True
Exit Sub
lbl:
If Err.Number = 6 Then MsgBox "Ïåðåïîëíåíèå", vbCritical, "Îøèáêà"
If Err.Number = 11 Then MsgBox "Äåëèòü íà íîëü íåëüçÿ", vbCritical, "Îøèáêà"
End Sub