三天不写代码就手生！ 把测试代码记录下来。
unit Unit1; interface uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls; type
TForm1 = class(TForm)
Button1: TButton;
Button2: TButton;
Button3: TButton;
Button4: TButton;
Memo1: TMemo;
CheckBox1: TCheckBox;
CheckBox2: TCheckBox;
procedure FormCreate(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
private
FFlag: Boolean;
public
{ Public declarations }
end; var
Form1: TForm1; implementation {$R *.dfm} procedure Log(Msg: string);
begin
TThread.Synchronize(nil, procedure
begin
Form1.Memo1.Lines.Add(Msg);
end);
end; procedure TForm1.Button1Click(Sender: TObject);
begin
//错误
if System.MonitorTryEnter(Form1) then
begin
System.MonitorEnter(Form1);
System.MonitorPulseAll(Form1);
System.MonitorExit(Form1);
end
else
Log('????');
end; procedure TForm1.Button2Click(Sender: TObject);
begin
//正确
System.MonitorPulseAll(Form1);
end; procedure TForm1.FormCreate(Sender: TObject);
var
AThread: TThread;
begin
FFlag := True;
TThread.CreateAnonymousThread(procedure
begin
while True do
begin
if Form1.CheckBox2.Checked then
Exit; if Form1.FFlag then
begin
System.MonitorEnter(Form1); //必须
Log('Thread1 Enter');
System.MonitorWait(Form1, INFINITE);
Log('Thread1 WaitFor');
System.MonitorExit(Form1); //必须
Log('Thread1 Exit');
end; Log(DateTimeToStr(Now));
TThread.Sleep();
end;
Log('Thread Exit');
end).Start; TThread.CreateAnonymousThread(procedure
begin
while True do
begin
if Form1.CheckBox2.Checked then
Exit; if Form1.FFlag then
begin
System.MonitorEnter(Form1);
Log('Thread2 Enter');
System.MonitorWait(Form1, INFINITE);
Log('Thread2 WaitFor');
System.MonitorExit(Form1);
Log('Thread2 Exit');
end; Log(DateTimeToStr(Now));
TThread.Sleep();
end;
Log('Thread Exit');
end).Start;
end; end.
注意事项：
1. 三个方法必须一块使用，不能只写 System.MonitorWait(Form1, INFINITE);
System.MonitorEnter(Form1); //必须
Log('Thread1 Enter');
System.MonitorWait(Form1, INFINITE);
Log('Thread1 WaitFor');
System.MonitorExit(Form1); //必须
Log('Thread1 Exit');
2. System.MonitorPulseAll(Form1) 即可。不要这样写
System.MonitorEnter(Form1);
System.MonitorPulseAll(Form1);
System.MonitorExit(Form1);