遇到这些问题时可以先看DELPHI HELP,觉得不够，可以看MSDN，网上搜。想要更深入了解
DELPHI是怎么包装的，就看DELPHI的源代码。
其实这个问题，DELPHI HELP已经很清楚了。
一：
Indicates the thread's handle (Windows only).
Delphi syntax:
property Handle: THandle;
C++ syntax:
__property int Handle = {read=FHandle, nodefault};
Description
On Windows, use Handle for calling Win32 API functions for thread manipulation.
The Handle property is not available on Linux.
handle就是线程的句柄。
二：
Identifies the thread throughout the system.
Delphi syntax:
On Windows:
property ThreadID: THandle;
On Linux:
property ThreadID: Cardinal;
C++ syntax:
On Windows:
__property int ThreadID = {read=FThreadID, nodefault};
On Linux:
__property unsigned int ThreadID = {read=FThreadID, nodefault};
Description
Use ThreadID, during debugging, to identify the thread in the Threads status box. On Windows, ThreadID is also useful when calling Win32 API functions for manipulating the thread.
Note: ThreadID is different than the thread抯 handle in the Handle property.
为了更加搞清楚ThreadID到底有什么用，我再查看一下DELPHI的TThread，
FHandle := begin
Thread(nil, 0, @ThreadProc, Pointer(Self), CREATE_SUSPENDED, FThreadID);
再跟进到system
function begin
Thread(SecurityAttributes: Pointer;
StackSize: LongWord;
ThreadFunc: TThreadFunc;
Parameter: Pointer;
CreationFlags: LongWord;
var ThreadId: LongWord): Integer;
var
P: PThreadRec;
begin
New(P);
P.Func := ThreadFunc;
P.Parameter := Parameter;
IsMultiThread := TRUE;
Result := CreateThread(SecurityAttributes, StackSize, @ThreadWrapper, P,
CreationFlags, ThreadID);
end;
这里的ThreadID带了VAR其实就是一个指针
再查MSDN
CreateThread
The CreateThread function creates a thread to execute within the virtual address space of the calling process.
To create a thread that runs in the virtual address space of another process, use the CreateRemoteThread function.
HANDLE CreateThread(
LPSECURITY_ATTRIBUTES lpThreadAttributes,
SIZE_T dwStackSize,
LPTHREAD_START_ROUTINE lpStartAddress,
LPVOID lpParameter,
DWORD dwCreationFlags,
LPDWORD lpThreadId
);
Parameters
lpThreadAttributes
[in] Pointer to a SECURITY_ATTRIBUTES structure that determines whether the returned handle can be inherited by child processes. If lpThreadAttributes is NULL, the handle cannot be inherited.
The lpSecurityDescriptor member of the structure specifies a security descriptor for the new thread. If lpThreadAttributes is NULL, the thread gets a default security descriptor. The ACLs in the default security descriptor for a thread come from the primary token of the creator.
Windows XP/2000/NT: The ACLs in the default security descriptor for a thread come from the primary or impersonation token of the creator. This behavior changed with Windows XP SP2 and Windows Server 2003.
dwStackSize
[in] Initial size of the stack, in bytes. The system rounds this value to the nearest page. If this parameter is zero, the new thread uses the default size for the executable. For more information, see Thread Stack Size.
lpStartAddress
[in] Pointer to the application-defined function to be executed by the thread and represents the starting address of the thread. For more information on the thread function, see ThreadProc.
lpParameter
[in] Pointer to a variable to be passed to the thread.
dwCreationFlags
[in] Flags that control the creation of the thread. If the CREATE_SUSPENDED flag is specified, the thread is created in a suspended state, and will not run until the ResumeThread function is called. If this value is zero, the thread runs immediately after creation.
If the STACK_SIZE_PARAM_IS_A_RESERVATION flag is specified, the dwStackSize parameter specifies the initial reserve size of the stack. Otherwise, dwStackSize specifies the commit size.
Windows 2000/NT and Windows Me/98/95: The STACK_SIZE_PARAM_IS_A_RESERVATION flag is not supported.
lpThreadId
[out] Pointer to a variable that receives the thread identifier. If this parameter is NULL, the thread identifier is not returned.
Windows Me/98/95: This parameter may not be NULL.
到这里应该清楚了，
这个参数用来接收线程的标识号的。NULL指示不需要返回值，而在ME、98、95这个参数可能不能为NULL。
在TThread中，使用了要求返回值，并放在TThreadID中。这样就可以兼容ME 98....了。
那DEPHI用这个FThreadID到底有什么作用呢？
destructor TThread.Destroy;
begin
if (FThreadID <> 0) and not FFinished then
begin
Terminate;
if FCreateSuspended then
Resume;
WaitFor;
end;
{$IFDEF MSWINDOWS}
if FHandle <> 0 then
CloseHandle(FHandle);
{$ENDIF}
代码我就不解释了。到这里应该非常明白了。
