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分享怎样取得CreateThread创建线程的函数的反回值
比如：
Dim hThread As Long, hThreadID As Long, Tcm As Long
MciCommand = "play C:\WINDOWS\Media\chimes.wav"
Lb = LoadLibrary("winmm.dll") '载入模块
ProcAdd = GetProcAddress(Lb, "mciExecute") '取得函数入口
hThread = CreateThread(ByVal 0&, ByVal 0&, ProcAdd, ByVal MciCommand, ByVal 0&, hThreadID) '创建线程
mciExecute这个函数会返回一个long的值，要怎样才可以取得
Dim hThread As Long, hThreadID As Long, Tcm As Long
MciCommand = "play C:\WINDOWS\Media\chimes.wav"
Lb = LoadLibrary("winmm.dll") '载入模块
ProcAdd = GetProcAddress(Lb, "mciExecute") '取得函数入口
hThread = CreateThread(ByVal 0&, ByVal 0&, ProcAdd, ByVal MciCommand, ByVal 0&, hThreadID) '创建线程
mciExecute这个函数会返回一个long的值，要怎样才可以取得
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舉杯邀明月 2017-12-23
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直接传给“线程”的参数，只能是1个，这是“约定”、是别人定好的“游戏规则”，
如果你“要走这条路”，那就是无法改变的事实！
但是，它不会去管你这“1个参数”具体的是什么含义。
也许这刚好是我需要传递的一个数据值；
也有可能什么都不是，只是因为“要填补空缺”而已，这个“参数”我根本就不需要……
以“Win32环境”来说（就比如VB6吧，其它开发环境也可以参考），那个“线程参数”是个“32位数”，
但需要传递“2个、或更多个参数”，是不能直接通过CreateThread( )传递的。
不过，其实“多个参数”，可以事先处理、放到一个“1维数组”中，而这个“线程参数”则是传递它的“数据首址”；
在“线程函数”中，按“约定顺序”和数据首址值，依次取出数据就行了。
当然这种情况需要“自己包装”一下，以便于正确接收及还原传入的参数，
肯定不能象你上面12楼那样，直接用到系统的（或其它第三方DLL的）API函数上。
用这种方式“包装”，别说三个参数，就是300个也没问题。并且可以是不同类型的参数混合的……
sxqvb 2017-12-23
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既然你这么励害，那你给我说说我想传多个叁数要怎么作呢
舉杯邀明月 2017-12-22
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我在上面已经说的很直接了。
都到这步程度了，竟然还说“不知道这是不是IsWindow这个函数的返回值”……
楼主，我建议你以后到CSDN，逛这个版块吧： http://bbs.csdn.net/forums/FreeZone
编程技术的版块不适合你。
楼主，我建议你以后到CSDN，逛这个版块吧： http://bbs.csdn.net/forums/FreeZone
编程技术的版块不适合你。sxqvb 2017-12-21
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Dim x As Long
x = Me.hwnd
Lb = LoadLibrary("user32.dll") '载入模块
ProcAdd = GetProcAddress(Lb, "IsWindow") '取得函数入口(判断是不是窗口)
hThread = CreateThread(ByVal 0&, ByVal 0&, ByVal ProcAdd, ByVal x, ByVal 0&, hThreadID) '创建线程
WaitObj = WaitForSingleObject(hThread, INFINITE) '等待线程结束
Dim Tcm As Long
GetExitCodeThread hThread, Tcm '取线程的反回值
Debug.Print Tcm
FreeLibrary Lb
赵4老师 2017-12-18
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《Windows核心编程》
《深入解析Windows操作系统-Windows Internals》
舉杯邀明月 2017-12-18
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已经把你“指引到门口”了，还不能明白，我也只能呵呵了…………
PctGL 2017-12-18
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说实话。。。 我觉得这种调用方式有点bt。。。
单开一个线程只为调用一个api，是为了异步吗？
而且常规方法肯定是不可能得到你想要的内容的
greatbody 2017-12-17
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楼主问的是，创建一个线程，调用线程中的函数，希望获取函数的返回值。
舉杯邀明月 2017-12-13
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看清楚：GetExitCodeThread → Get Exit Code Threaed
简单的“望文生义”，也知道不是“取线程状态”啊…………
自己看看“百度百科”中的介绍啊，那是中文的，你不会说“不认识汉字”吧。
自己看看“百度百科”中的介绍啊，那是中文的，你不会说“不认识汉字”吧。
sxqvb 2017-12-13
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出差才回来
Private Declare Function CreateThread Lib "kernel32" (lpThreadAttributes As Any, ByVal dwStackSize As Long, ByVal lpStartAddress As Long, lpParameter As Any, ByVal dwCreationFlags As Long, lpThreadId As Long) As Long
这是CreateThread 定义，和你说的一样
GetExitCodeThread这个不是取线程状态的函数吗
我想问的是: GetExitCodeThread 创建了一个线程，这个线程调用了 mciExecute 这个API，现在需要得到 mciExecute 这个的返回值
赵4老师 2017-12-05
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CreateThread
The CreateThread function creates a thread to execute within the address space of the calling process.
HANDLE CreateThread(
LPSECURITY_ATTRIBUTES lpThreadAttributes, // pointer to security attributes
DWORD dwStackSize, // initial thread stack size
LPTHREAD_START_ROUTINE lpStartAddress, // pointer to thread function
LPVOID lpParameter, // argument for new thread
DWORD dwCreationFlags, // creation flags
LPDWORD lpThreadId // pointer to receive thread ID
);
Parameters
lpThreadAttributes
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.
Windows NT: 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.
dwStackSize
Specifies the initial commit size of the stack, in bytes. The system rounds this value to the nearest page. If this value is zero, or is smaller than the default commit size, the default is to use the same size as the calling thread. For more information, see Thread Stack Size.
lpStartAddress
Pointer to the application-defined function of type LPTHREAD_START_ROUTINE to be executed by the thread and represents the starting address of the thread. For more information on the thread function, see ThreadProc.
lpParameter
Specifies a single 32-bit parameter value passed to the thread.
dwCreationFlags
Specifies additional 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. At this time, no other values are supported.
lpThreadId
Pointer to a 32-bit variable that receives the thread identifier.
Windows NT: If this parameter is NULL, the thread identifier is not returned.
Windows 95 and Windows 98: This parameter may not be NULL.
Return Values
If the function succeeds, the return value is a handle to the new thread.
If the function fails, the return value is NULL. To get extended error information, call GetLastError.
Windows 95 and Windows 98: CreateThread succeeds only when it is called in the context of a 32-bit program. A 32-bit DLL cannot create an additional thread when that DLL is being called by a 16-bit program.
Remarks
The new thread handle is created with THREAD_ALL_ACCESS to the new thread. If a security descriptor is not provided, the handle can be used in any function that requires a thread object handle. When a security descriptor is provided, an access check is performed on all subsequent uses of the handle before access is granted. If the access check denies access, the requesting process cannot use the handle to gain access to the thread.
The thread execution begins at the function specified by the lpStartAddress parameter. If this function returns, the DWORD return value is used to terminate the thread in an implicit call to the ExitThread function. Use the GetExitCodeThread function to get the thread's return value.
The CreateThread function may succeed even if lpStartAddress points to data, code, or is not accessible. If the start address is invalid when the thread runs, an exception occurs, and the thread terminates. Thread termination due to a invalid start address is handled as an error exit for the thread's process. This behavior is similar to the asynchronous nature of CreateProcess, where the process is created even if it refers to invalid or missing dynamic-link libraries (DLLs).
The thread is created with a thread priority of THREAD_PRIORITY_NORMAL. Use the GetThreadPriority and SetThreadPriority functions to get and set the priority value of a thread.
When a thread terminates, the thread object attains a signaled state, satisfying any threads that were waiting on the object.
The thread object remains in the system until the thread has terminated and all handles to it have been closed through a call to CloseHandle.
The ExitProcess, ExitThread, CreateThread, CreateRemoteThread functions, and a process that is starting (as the result of a call by CreateProcess) are serialized between each other within a process. Only one of these events can happen in an address space at a time. This means that the following restrictions hold:
During process startup and DLL initialization routines, new threads can be created, but they do not begin execution until DLL initialization is done for the process.
Only one thread in a process can be in a DLL initialization or detach routine at a time.
ExitProcess does not return until no threads are in their DLL initialization or detach routines.
A thread that uses functions from the C run-time libraries should use the beginthread and endthread C run-time functions for thread management rather than CreateThread and ExitThread. Failure to do so results in small memory leaks when ExitThread is called.
Windows CE: The lpThreadAttributes parameter must be set to NULL. The dwStackSize parameter must be zero. Only zero or CREATE_SUSPENDED values are supported for the dwCreationFlags parameter.
QuickInfo
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.01 or later.
Header: Declared in winbase.h.
Import Library: Use kernel32.lib.
See Also
Processes and Threads Overview, Process and Thread Functions, CloseHandle, CreateProcess, CreateRemoteThread, ExitProcess, ExitThread, GetExitCodeThread, GetThreadPriority, ResumeThread, SetThreadPriority, SECURITY_ATTRIBUTES, ThreadProc
舉杯邀明月 2017-12-04
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CreateThread( ) 的“第三个参数”，是“输入参数”，不是用来“返回数据”的！
注意：VB6的“API浏览器”带的声明信息 Win32API.txt ，它的第3个参数形式声明是错误的（某些“修改版”同样的错误）！
VB6中应该加上 ByVal 才对！在Win32API.txt中是没有指定“传递方式”的，那就是默认的ByRef传递。
若不更正，如果要“正确传递”，那么就要在调用CreateThread( ) 语句的第3个参数前加ByVal，
否则传入的不是“函数地址”，而是传入的“变量地址”或“临时变量的地址”了。
可以查阅MSDN，仔细“理解”那个参数的作用，可以看到它是“输入”用的、是“函数入口首址”。
你要得到那个“函数返回值”，就是需要通过我在楼上说的那个API函数 ！
在线程创建成功、并且线程函数被正常执行完成后，这个“函数”就有一个“返回值”，
而这个值就需要用 GetExitCodeThread( ) 才能获取！
注意：VB6的“API浏览器”带的声明信息 Win32API.txt ，它的第3个参数形式声明是错误的（某些“修改版”同样的错误）！
VB6中应该加上 ByVal 才对！在Win32API.txt中是没有指定“传递方式”的，那就是默认的ByRef传递。
若不更正，如果要“正确传递”，那么就要在调用CreateThread( ) 语句的第3个参数前加ByVal，
否则传入的不是“函数地址”，而是传入的“变量地址”或“临时变量的地址”了。
可以查阅MSDN，仔细“理解”那个参数的作用，可以看到它是“输入”用的、是“函数入口首址”。
你要得到那个“函数返回值”，就是需要通过我在楼上说的那个API函数 ！
在线程创建成功、并且线程函数被正常执行完成后，这个“函数”就有一个“返回值”，
而这个值就需要用 GetExitCodeThread( ) 才能获取！sxqvb 2017-12-03
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不是的，我不是要CreateThread这个的返回值，我是想要CreateThread调用的函数的返回值，也是就CreateThread的第三个参数对应的函数的返回值。
舉杯邀明月 2017-12-03
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Function GetExitCodeThread Lib "Kernel32" (ByVal hThread As Long, ByRef ExitCode As Long) As Long
如果API调用执行成功，ExitCode的返回值是 STILL_ACTIVE 表示线程还没有结束（还在执行中）。
舉杯邀明月 2017-12-03
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API函数： GetExitCodeThread( )
楼主查一下相差信息吧。
