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转载自:万一的博客
一下子跳到等待函数 WaitForSingleObject,是因为下面的Mutex、Semaphore、Event、WaitableTimer等同步手段都要使用这个函数。不过等待函数可不止WaitForSingleObject这一个,但是它是最简单的
function WaitForSingleObject(
hHandle: THandle; //要等待的对象句柄
dwMillseconds: DWORD; //等待的时间,单位是毫秒
): DWORD; srdcall;
返回值说明如下
WAIT_OBJECT_0 {等着了,本例中是:等的那个进程终于结束了}
WAIT_TIMEOUT {等过了点(你指定的时间),也没等着}
WAIT_ABANDONED {好不容易等着了,但是人家还是不让咱执行;这一般是互斥对象}
//WaitForSingleObject 的第二个参数一般给常数值 INFINITE, 表示一直等下去, 死等.
WaitForSingleObject等待什么?在多线程就是等待另一个线程的结束,快来执行自己的代码;不过他可以等待的对象可不止线程;这里先来一个等待另一个进程结束的例子,运行效果图

代码如下
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;
type
TForm1=class(TForm)
Button1: TButton;
procedure Button1Click(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
var
hProcess: Thandle; {进程句柄}
{等待一个指定句柄的进程什么时候结束}
function MyThreadFun(p: Pointer);DWORD;stdcall;
begin
if WaitForSingleObject(hProcess, INFINITE)=WAIT_OBJECT_0 then
Form1.Text:= Format(‘进程 %d 已关闭‘,[hProcess]);
Result:= 0;
end;
procedure TForm1.Button1Click(Sender: Tobject);
var
pInfo: TProcessInformation;
sInfo: TStartupInfo;
Path: Array[0..MAX_PATH-1] of Char;
ThreadID: DWORD;
begin
{先获得记事本的路径}
GetSystemDirectory(Path, MAX_PATH);
StrCat(Path, ‘\notepad.exe‘);
{用 CreateProcess 打开记事本并获取进程句柄,然后建立线程监视}
FillChar(sInfo, SizeOf(sInfo),0);
if CreateProcess(Path, nil, nil, nil, False, 0, nil, nil, sInfo, pInfo) then
begin
hProcess:= pInfo.hProcess; //获取进程句柄
Text:= Format(‘进程 %d 已启动‘, [hProcess]);
CreateThread(nil, 0, @MyThreadFun, nil, 0, ThreadID); //建立线程监视
end;
end;
end.
窗体文件
object Form1: TForm1
Left = 0
Top = 0
Caption = ‘Form1‘
ClientHeight = 124
ClientWidth = 241
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = ‘Tahoma‘
Font.Style = []
OldCreateOrder = False
PixelsPerInch = 96
TextHeight = 13
object Button1: TButton
Left = 88
Top = 56
Width = 75
Height = 25
Caption = ‘Button1‘
TabOrder = 0
OnClick = Button1Click
end
end
Delphi多线程编程(9)--认识等待函数WaitForSingleObject
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原文地址:http://www.cnblogs.com/xumenger/p/4493675.html