vba - 阶乘函数返回平方数而不是阶乘

Question

我的代码哪里错了？它返回任何数字的平方:

Sub factorial()
Dim x As Long, i As Integer, fact As Long
   x = InputBox("enter the integer")
   For i = 1 To x
      fact = i * x
      Next i
   MsgBox fact
End Sub 

Answer 1

练习循环和 If声明!？

Option Explicit

' If you are practicing (loops) then:
Sub factorial()
    Dim x As Long, i As Long, fct As Double
    x = InputBox("enter the integer")
    If x >= 0 And x <= 170 Then
        fct = 1
        If x > 1 Then
            For i = 2 To x
                fct = fct * i
            Next i
        End If
        MsgBox fct
    Else
        MsgBox "Next time enter a number between 0 and 170."
        Exit Sub
    End If
End Sub

' ...if not, just use Fact
Sub factorialExcel()
    Dim x As Long
    x = InputBox("enter the integer")
    If x >= 0 And x <= 170 Then
        MsgBox Application.WorksheetFunction.Fact(x)
    Else
        MsgBox "Next time enter a number between 0 and 170."
        Exit Sub
    End If
End Sub