command 属性设置 - 编程论坛

#2

lianyicq2015-03-10 10:10

试试设一布尔型全程变量pause，初值为false，窗体上新建一按钮，点击按钮后pause=true

Dim pause As Boolean
Dim i As Long
Private Sub Command1_Click()
  pause = Not (pause)
  If pause = False Then Form1.Caption = i
End Sub

Private Sub Form_Load()
  Me.Show
  While (1)
    DoEvents
    If pause = False Then
       i = i + 1
    End If
  Wend
End Sub

#3

a5350804592015-03-10 10:58

回复 2楼 lianyicq

请问版主大大，假如我程序里有一个 Do...loop 循环，改怎么处理呢？如下：
Dim pause As Boolean
Private Declare Sub Sleep Lib "kernel32.DLL" (ByVal dwMilliseconds As Long)
Dim i As Long
Private Sub Command1_Click()
  pause = Not (pause)
  If pause = False Then
  'Form1.Caption = i
  Do
  Sleep (1000)
  Print i
  Loop
End Sub

Private Sub Form_Load()
  Me.Show
  While (1)
    DoEvents
    If pause = False Then
       i = i + 1
    End If
  Wend
End Sub

再次点击 Command1 的话会发生程序停止但窗体无法响应。但我不知道程序是因pause = False停止下来的，还是因为窗体无响应导致程序停下来的。主要问题是怎么才能退出 Do 循环呢？

#4

lianyicq2015-03-10 11:30

程序代码：

Dim pause As Boolean
Private Declare Sub Sleep Lib "kernel32.DLL" (ByVal dwMilliseconds As Long)
Dim i As Long
Dim CMD_Exit As Boolean

Private Sub Command1_Click()
  pause = Not (pause)
  Command1.Caption = "已暂停"
  If pause = False Then CMD_Exit = True
End Sub

Private Sub Form_Load()
  Me.Show
  Do
  If CMD_Exit = True Then Command1.Caption = "已退出循环": Command1.Enabled = False: Exit Sub
  DoEvents
  Form1.Caption = "Pause"
  If pause = False Then
     Form1.Caption = "Executing"
     Sleep (1000)
     Print i
  End If
  Loop
End Sub

#5

a5350804592015-03-10 13:41

非常非常感谢 lianyicq版主大大！

你太强了！

无限崇拜啊！问题已经解决了，像我这种水平适合看哪些书籍资料或者大大有没有个人视频讲解什么的。小白本人正在自学“Visual Basic vb编程从入门到精通(第3版) ”，还有什么大大可指导的？