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转载自：万一的博客
function CreateThread(
lpThreadAttributes: Pointer;
dwStackSize: DWORD;
lpStartAddress: TFNThreadStartRoutine;
lpParameter: Pointer;
dwCreationFlags: DWORD; {启动选项}
var lpThreadId: DWORD
): THandle; stdcall;
CreateThread的倒数第二个参数dwCreateFlasg（启动选项）有两个可选值
0：线程建立后立即执行入口函数
CREATE_SUSPENDED：线程建立后会挂起等待
可以ResumeThread 函数恢复线程的运行；可用 SuspendThread再次挂起线程。这两个函数的参数都是线程句柄，返回值都是执行前的挂起计数
什么是挂起计数？
SuspendThread会个这个数+1， ResumeThread会给这个数-1；但是这个数最小是0。如果这个数是0，线程会运行； >0 时会挂起。所以如果被SuspendThread 多次，同样需要ResumeThread 多次才能恢复线程的运行
下面的例子中，有新线程不断给一个全局变量赋随机值
同时窗体上的Timer 控件每隔 1/10秒就把这个变量写在窗体标题
在这个过程中演示了ResumeThread 和SuspendThread这两个函数，运行效果图如下
代码如下
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls;
type
TForm1=class(TForm)
Button1: TButton;
Button2: TButton;
Button3: TButton;
Timer1: TTimer;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure Button3Click(Sender: TObject);
procedure FormCreate(Sender: TObject);
procedure Timer1Timer(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
var
hThread: THandle; //线程句柄
num: Integer; //全局变量，用于记录随机数
{线程入口函数}
function MyThreadFun(p: Pointer): Integer; stdcall;
begin
while True do
begin
num:= Random(100);
end;
Result:= 0;
end;
{建立并挂起线程}
procedure TForm1.Button1Click(Sender: TObject);
var
ID: DWORD;
begin
hThread:= CreateThread(nil, 0, @MyThreadFun, nil, CREATE_SUSPENDED, ID);
Button1.Enabled:= False;
end;
{唤醒并继续线程}
procedure TForm1.Button2Click(Sender: TObject);
begin
ResumeThread(hThread);
end;
{挂起线程}
procedure TForm1.Button3Click(Sender: TObject);
begin
SuspendThread(hThread);
end;
{下面是窗体代码}
procedure TForm1.FormCreate(Sender: TObject);
begin
Timer1.Interval:= 100;
end;
procedure TForm1.Timer1Timer(Sender: TObject);
begin
Text:= IntToStr(num);
end;
end.
下面是窗体文件
object Form1: TForm1
Left = 0
Top = 0
Caption = ‘Form1‘
ClientHeight = 86
ClientWidth = 269
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = ‘Tahoma‘
Font.Style = []
OldCreateOrder = False
OnCreate = FormCreate
PixelsPerInch = 96
TextHeight = 13
object Button1: TButton
Left = 16
Top = 24
Width = 75
Height = 25
Caption = ‘Button1‘
TabOrder = 0
OnClick = Button1Click
end
object Button2: TButton
Left = 97
Top = 24
Width = 75
Height = 25
Caption = ‘Button2‘
TabOrder = 1
OnClick = Button2Click
end
object Button3: TButton
Left = 178
Top = 24
Width = 75
Height = 25
Caption = ‘Button3‘
TabOrder = 2
OnClick = Button3Click
end
object Timer1: TTimer
OnTimer = Timer1Timer
end
end
ResumeThread 和SuspendThread 分别对应 TThread的Resume 和 Suspend 方法，很好理解
接下来应该是 CreateThread的第四个参数了（也就是倒数第三个参数）
多线程编程(3)--从CreateThread说起（倒数第二个参数）
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原文地址：http://www.cnblogs.com/xumenger/p/4487477.html
