Question

VB 为什么Print出来的第二行是0，第三行是4 a（1）不应该 = f（1）= 2 a（4）= f（4）= 5 么？

代码：

Private Sub Command1_Click()
Dim a(6) As Integer
Dim x As Integer, i As Integer
Print f(2)
For i = 1 To 5
a(i) = f(i)
Next i
Print a(1)
Print a(4)
End Sub
Function f(x As Integer)
x = x + 1
f = x
End Function

Answer 1

Private Sub Command1_Click()
Dim a(6) As Integer
Dim x As Integer, i As Integer
Print f(2)
For i = 1 To 5
Debug.Print i, '增加这两句，在立即窗口中看打印内容就知道了
a(i) = f(i)
Debug.Print a(i), i '增加这两句，在立即窗口中看打印内容就知道了
Next i
Print a(1)
Print a(4)
End Sub
Function f(x As Integer)
x = x + 1
f = x
End Function
'立即窗口打印结果：
' 1 2 2 i=1时，经过f函数，变为2，未给a(1)赋值，所以为0
' 3 4 4
' 5 6 6