小弟我现在想通过byref将几个参数从函数传出去，试验了这个最简单的小程序。为什么会出错

我现在想通过byref将几个参数从函数传出去，试验了这个最简单的小程序。为什么会出错！
Private   Sub   Form_Load()


        Dim   a,   b,   c   As   Integer
        a   =   1
        b   =   8
       
       
          Call   swap(a,   b)
       
       
        Debug.Print   "a= "   &   a,   "b= "   &   b


End   Sub


Private   Sub   swap(ByRef   a   As   Integer,   ByRef   b   As   Integer)
       
        Dim   temp   As   Integer
       
        temp   =   a
        a   =   b
        b   =   temp
       

End   Sub


------解决方案--------------------
Private Sub Form_Load()

Dim a As Integer, b As Integer, c As Integer
a = 1
b = 8

Call swap(a, b)

Debug.Print "a= " & a, "b= " & b

End Sub


Private Sub swap(ByRef a As Integer, ByRef b As Integer)

Dim temp As Integer

temp = a
a = b
b = temp

End Sub

问题出在定义变量上了
VB中定义多个变量不能像楼主那样的
dim a as integer,b as integer,c as double,d as string,e as single