程序代码：

Private Sub Command1_Click()
Dim i As Long, j As Long, k As Long, Total As Long

    i = Val(Text1.Text)
    Total = 0

    Do While i > 0
        k = 1
        For j = i To 1 Step -1
            k = k * j
        Next j
        Total = Total + k
        i = i - 1
    Loop

 
    MsgBox Total
    Text1.Text = ""
End Sub

程序代码：

Private Sub Command1_Click()
Dim i As Long

    i = Val(Text1.Text)

    MsgBox AAA(i)
    
    Text1.Text = ""
    
End Sub

Private Function AAA(i As Long) As Long
Dim j As Long, k As Long, Total As Long

    Total = 0

    Do While i > 0
        k = 1
        For j = i To 1 Step -1
            k = k * j
        Next j
        Total = Total + k
        i = i - 1
    Loop
    
    AAA = Total

End Function

程序代码：

Private Sub Command1_Click()
Dim i As Long, j As Long, k As Long

    i = Val(Text1.Text)

    MsgBox AAA(i)
    
    Text1.Text = ""
    
End Sub

Private Function AAA(i As Long) As Long
Dim j As Long, k As Long

    Do While i > 0
        k = 1
        For j = i To 1 Step -1
            k = k * j
        Next j
        AAA = AAA + k
        i = i - 1
    Loop

End Function