昨天做了个计算器，减法乘法除法都可以，就是加法1+1=11  5+5=55.求各位大大帮帮忙

Private Sub Command1_Click()
Text3 = Text1 + Text2
Dim a As String
a = "计算中...  "
MsgBox a
End Sub
------------------
Private Sub Command2_Click()
Text3 = Text1 - Text2
Dim a As String
a = "计算中... "
MsgBox a
End Sub
-----------
Private Sub Command3_Click()
Text3 = Text1 * Text2
Dim a As String
a = "计算中...  "
MsgBox a
End Sub
------------
Private Sub Command4_Click()
Text3 = Text1 / Text2
Dim a As String
a = "计算中...  "
MsgBox a
End Sub
------------
Private Sub Form_Load()
Dim a As String
a = "欢迎试用10进制计算器，廖将豪制作 "
MsgBox a
End Sub
----------
Private Sub Label1_Click()

End Sub
---------------
Private Sub Text1_Change()

End Sub
是代码

那里有错误啊？

谢谢啊

Private Sub Command1_Click()
Text3 = Val(Text1) + Val(Text2)
Dim a As String
a = "计算中...  "
MsgBox a
End Sub

Private Sub Command1_Click()
Text3 = Text1+ Text2
Dim a As String
a = "计算中...  "
MsgBox a
End Sub
为什么乘法减法和除法可以，而加法不行呢？

谢谢