任意5个数相加，在VB中的语言是怎么编写的呢？

那就更简单了：
Private Sub Form_click()
Dim n As Single, sum As Single
sum = 0
For i = 1 To 5
n = InputBox("请输入第" & i & "个数", "输入框")
sum = sum + n
Next
Print "这五个数之和为："; sum
End Sub

加一个Command1
Private Sub Command1_Click()
Dim a(5), sum As Long
Dim i As Integer
For i = 0 To 4
a(i) = Int((10 * Rnd) + 1) ' 生成 1 到 10 之间的随机数值
sum = sum + a(i)
Next
Print sum
End Sub