ByVal 与 ByRef(默认值) 的区别

'ByVal 与 ByRef(默认值) 的区别

'ByVal 按值传递 不改变实参

'ByRef 按地址传递 改变实参

Private Sub Form_Load()

Me.Show

Dim A As Integer, B As Integer

A = 1

B = 2

Call AAA(A, B)

Print A, B '得到的结果是2,3

A = 1

B = 2

Call BBB(A, B)

Print A, B '得到的结果是1, 2

End Sub

Sub AAA(I As Integer, J As Integer) '默认,则按址传递

I = I + 1

J = J + 1

End Sub

Sub BBB(ByVal I As Integer, ByVal J As Integer)

I = I + 1

J = J + 1

End Sub