VB题。将用户输入的三个数字按照从小到大获从大到小的顺序排序，排序方式可由用户设置。 程序怎么写呢

这里有两种方法。第一种，直接交换，代码比较多，容易出错。

第二种，把交换部分写成一个独立过程，中间调用。便于阅读，书写方便，不易出错。

用户的关于从大到小和从小到大排序选择，使用Option控件（）如图。

Private Sub Command1_Click()
    Dim a As Integer
    Dim b As Integer
    Dim c As Integer
    Dim tmp As Integer
    a = Val(Text1.Text)
    b = Val(Text2.Text)
    c = Val(Text3.Text)
    If Option1.Value = True Then
        If a < b Then
            tmp = a
            a = b
            b = tmp
        End If
        If c > a Then
            tmp = b
            b = c
            c = tmp
            tmp = a
            a = b
            b = tmp
        ElseIf c > b Then
            tmp = b
            b = c
            c = tmp
        End If
    Else
        If a > b Then
            tmp = a
            a = b
            b = tmp
        End If
        If c < a Then
            tmp = b
            b = c
            c = tmp
            tmp = a
            a = b
            b = tmp
        ElseIf c < b Then
            tmp = b
            b = c
            c = tmp
        End If
    End If
    Text1.Text = CStr(a)
    Text2.Text = CStr(b)
    Text3.Text = CStr(c)
   
End Sub

Sub swap(x, y)
    Dim tmp
    tmp = x
    x = y
    y = tmp
End Sub

Private Sub Command2_Click()
    Dim a As Integer
    Dim b As Integer
    Dim c As Integer
    Dim tmp As Integer
    a = Val(Text1.Text)
    b = Val(Text2.Text)
    c = Val(Text3.Text)
    If Option1.Value = True Then
        If a < b Then
        End If
        If c > a Then
            swap b, c
            swap a, b
        ElseIf c > b Then
            swap b, c
        End If
    Else
        If a > b Then
            swap a, b
        End If
        If c < a Then
            swap b, c
            swap a, b
        ElseIf c < b Then
            swap b, c
        End If
    End If
    Text1.Text = CStr(a)
    Text2.Text = CStr(b)
    Text3.Text = CStr(c)
   
End Sub