想做一个倒计时显示，点击按钮在text上显示倒计时数字，功能是实现了，但是只能点一次，下一次点击就不动作了。求教！（PPT中的vba）

Private Sub CommandButton1_Click()
If CommandButton1.Caption <> "开始" Then
CommandButton1.Caption = "开始"
Else
CommandButton1.Caption = "结束"
i = 10
Label1.Caption = 10
Do While i > 0
DoEvents
Label1.Caption = i
i = i - 1
Application.Wait (Now + TimeValue("00:00:01"))
If i = 0 Or CommandButton1.Caption = "开始" Then
CommandButton1.Caption = "开始"
Exit Sub
End If
Loop
End If
End Sub

blog.csdn.net/weixin_44386796/article/details/140840513?spm=1001.2014.3001.5502
这个是我写的，你参考一下