VB啊啊啊

来源：百度知道编辑：UC知道时间：2024/06/12 17:08:39

通过文本框输入一个数值，判断该数是正数、负数还是0，并把运算结果在标签控件上显示出来。要求用Select Case语句实现。

Private Sub Text1_Change()
a = Val(Text1.Text)
Select Case a
Case Is > 0
Label1.Caption = "正数"
Case Is = 0
Label1.Caption = "0"
Case Is < 0
Label1.Caption = "负数"
End Select
End Sub

Dim a As Integer
Try
a = TextBox1.Text
Select Case a
Case Is > 0
MessageBox.Show("正数")
Case Is < 0
MessageBox.Show("负数")
Case Is = 0
MessageBox.Show("0")
End Select
Catch
MessageBox.Show("非数值")
End Try