win32手动创建windows窗口的，小记

摘抄自文档，其中的函数需要以后花时间看

向 WinMain 添加功能

首先，在 WinMain 函数内部创建 WNDCLASSEX 类型的窗口类结构。此结构包含有关窗口的信息，如应用程序图标、窗口的背景色、在标题栏中显示的名称、窗口过程函数的名称等等。典型的 WNDCLASSEX 结构如下：

    WNDCLASSEX wcex;

    wcex.cbSize = sizeof(WNDCLASSEX);

    wcex.style          = CS_HREDRAW | CS_VREDRAW;

    wcex.lpfnWndProc    = WndProc;

    wcex.cbClsExtra     = 0;

    wcex.cbWndExtra     = 0;

    wcex.hInstance      = hInstance;

    wcex.hIcon          = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);

    wcex.hbrBackground  = (HBRUSH)(COLOR_WINDOW+1);

    wcex.lpszMenuName   = NULL;

    wcex.lpszClassName  = szWindowClass;

    wcex.hIconSm        = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

    WNDCLASSEX wcex;

    wcex.cbSize = sizeof(WNDCLASSEX);

    wcex.style          = CS_HREDRAW | CS_VREDRAW;

    wcex.lpfnWndProc    = WndProc;

    wcex.cbClsExtra     = 0;

    wcex.cbWndExtra     = 0;

    wcex.hInstance      = hInstance;

    wcex.hIcon          = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);

    wcex.hbrBackground  = (HBRUSH)(COLOR_WINDOW+1);

    wcex.lpszMenuName   = NULL;

    wcex.lpszClassName  = szWindowClass;

    wcex.hIconSm        = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

有关此结构的字段解释，请参见 WNDCLASSEX。

现在已经创建了窗口类，接下来您必须注册它。使用 RegisterClassEx 函数，并将窗口类结构作为参数传递：

    if (!RegisterClassEx(&wcex))

    {

        MessageBox(NULL,

            _T("Call to RegisterClassEx failed!"),

            _T("Win32 Guided Tour"),

            NULL);

        return 1;

    }

    if (!RegisterClassEx(&wcex))

    {

        MessageBox(NULL,

            _T("Call to RegisterClassEx failed!"),

            _T("Win32 Guided Tour"),

            NULL);

        return 1;

    }

现在已经注册了您自己的类，接下来创建窗口。使用 CreateWindow 函数，如下所示：

static TCHAR szWindowClass[] = _T("win32app");

static TCHAR szTitle[] = _T("Win32 Guided Tour Application");

// The parameters to CreateWindow explained:

// szWindowClass: the name of the application

// szTitle: the text that appears in the title bar

// WS_OVERLAPPEDWINDOW: the type of window to create

// CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y)

// 500, 100: initial size (width, length)

// NULL: the parent of this window

// NULL: this application dows not have a menu bar

// hInstance: the first parameter from WinMain

// NULL: not used in this application

HWND hWnd = CreateWindow(

    szWindowClass,

    szTitle,

    WS_OVERLAPPEDWINDOW,

    CW_USEDEFAULT, CW_USEDEFAULT,

    500, 100,

    NULL,

    NULL,

    hInstance,

    NULL

);

if (!hWnd)

{

    MessageBox(NULL,

        _T("Call to CreateWindow failed!"),

        _T("Win32 Guided Tour"),

        NULL);

    return 1;

}

static TCHAR szWindowClass[] = _T("win32app");

static TCHAR szTitle[] = _T("Win32 Guided Tour Application");

// The parameters to CreateWindow explained:

// szWindowClass: the name of the application

// szTitle: the text that appears in the title bar

// WS_OVERLAPPEDWINDOW: the type of window to create

// CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y)

// 500, 100: initial size (width, length)

// NULL: the parent of this window

// NULL: this application dows not have a menu bar

// hInstance: the first parameter from WinMain

// NULL: not used in this application

HWND hWnd = CreateWindow(

    szWindowClass,

    szTitle,

    WS_OVERLAPPEDWINDOW,

    CW_USEDEFAULT, CW_USEDEFAULT,

    500, 100,

    NULL,

    NULL,

    hInstance,

    NULL

);

if (!hWnd)

{

    MessageBox(NULL,

        _T("Call to CreateWindow failed!"),

        _T("Win32 Guided Tour"),

        NULL);

    return 1;

}

此函数返回 HWND，它是某个窗口的句柄。有关更多信息，请参见 Windows 数据类型。

创建了窗口后，我们可以使用以下代码将其显示在屏幕上：

// The parameters to ShowWindow explained:

// hWnd: the value returned from CreateWindow

// nCmdShow: the fourth parameter from WinMain

ShowWindow(hWnd,

    nCmdShow);

UpdateWindow(hWnd);

// The parameters to ShowWindow explained:

// hWnd: the value returned from CreateWindow

// nCmdShow: the fourth parameter from WinMain

ShowWindow(hWnd,

    nCmdShow);

UpdateWindow(hWnd);

到目前为止，此窗口还不会显示，因为我们尚未实现 WndProc 函数。

WinMain 的最后一步是消息循环。此循环的用途是侦听操作系统发送的消息。应用程序收到消息后，将该消息调度到 WndProc 函数，以便进行处理。消息循环类似于：

以带有颜色区分的格式查看复制到剪贴板打印

    MSG msg;

    while (GetMessage(&msg, NULL, 0, 0))

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }

    return (int) msg.wParam;

    MSG msg;

    while (GetMessage(&msg, NULL, 0, 0))

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }

    return (int) msg.wParam;

有关消息循环中使用的结构和函数的更多信息，请参见 MSG、 GetMessage、 TranslateMessage 和 DispatchMessage。

您刚才完成的步骤为大多数 Win32 应用程序所共用。有关此应用程序所需要的 include 指令和全局变量声明，请参见本主题末尾的完整代码示例。

此时， WinMain 函数应该与下面的内容类似：

int WINAPI WinMain(HINSTANCE hInstance,

                   HINSTANCE hPrevInstance,

                   LPSTR lpCmdLine,

                   int nCmdShow)

{

    WNDCLASSEX wcex;

    wcex.cbSize = sizeof(WNDCLASSEX);

    wcex.style          = CS_HREDRAW | CS_VREDRAW;

    wcex.lpfnWndProc    = WndProc;

    wcex.cbClsExtra     = 0;

    wcex.cbWndExtra     = 0;

    wcex.hInstance      = hInstance;

    wcex.hIcon          = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);

    wcex.hbrBackground  = (HBRUSH)(COLOR_WINDOW+1);

    wcex.lpszMenuName   = NULL;

    wcex.lpszClassName  = szWindowClass;

    wcex.hIconSm        = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

    if (!RegisterClassEx(&wcex))

    {

        MessageBox(NULL,

            _T("Call to RegisterClassEx failed!"),

            _T("Win32 Guided Tour"),

            NULL);

        return 1;

    }

    hInst = hInstance; // Store instance handle in our global variable

    // The parameters to CreateWindow explained:

    // szWindowClass: the name of the application

    // szTitle: the text that appears in the title bar

    // WS_OVERLAPPEDWINDOW: the type of window to create

    // CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y)

    // 500, 100: initial size (width, length)

    // NULL: the parent of this window

    // NULL: this application dows not have a menu bar

    // hInstance: the first parameter from WinMain

    // NULL: not used in this application

    HWND hWnd = CreateWindow(

        szWindowClass,

        szTitle,

        WS_OVERLAPPEDWINDOW,

        CW_USEDEFAULT, CW_USEDEFAULT,

        500, 100,

        NULL,

        NULL,

        hInstance,

        NULL

    );

    if (!hWnd)

    {

        MessageBox(NULL,

            _T("Call to CreateWindow failed!"),

            _T("Win32 Guided Tour"),

            NULL);

        return 1;

    }

    // The parameters to ShowWindow explained:

    // hWnd: the value returned from CreateWindow

    // nCmdShow: the fourth parameter from WinMain

    ShowWindow(hWnd,

        nCmdShow);

    UpdateWindow(hWnd);

    // Main message loop:

    MSG msg;

    while (GetMessage(&msg, NULL, 0, 0))

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }

    return (int) msg.wParam;

}

int WINAPI WinMain(HINSTANCE hInstance,

                   HINSTANCE hPrevInstance,

                   LPSTR lpCmdLine,

                   int nCmdShow)

{

    WNDCLASSEX wcex;

    wcex.cbSize = sizeof(WNDCLASSEX);

    wcex.style          = CS_HREDRAW | CS_VREDRAW;

    wcex.lpfnWndProc    = WndProc;

    wcex.cbClsExtra     = 0;

    wcex.cbWndExtra     = 0;

    wcex.hInstance      = hInstance;

    wcex.hIcon          = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);

    wcex.hbrBackground  = (HBRUSH)(COLOR_WINDOW+1);

    wcex.lpszMenuName   = NULL;

    wcex.lpszClassName  = szWindowClass;

    wcex.hIconSm        = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

    if (!RegisterClassEx(&wcex))

    {

        MessageBox(NULL,

            _T("Call to RegisterClassEx failed!"),

            _T("Win32 Guided Tour"),

            NULL);

        return 1;

    }

    hInst = hInstance; // Store instance handle in our global variable

    // The parameters to CreateWindow explained:

    // szWindowClass: the name of the application

    // szTitle: the text that appears in the title bar

    // WS_OVERLAPPEDWINDOW: the type of window to create

    // CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y)

    // 500, 100: initial size (width, length)

    // NULL: the parent of this window

    // NULL: this application dows not have a menu bar

    // hInstance: the first parameter from WinMain

    // NULL: not used in this application

    HWND hWnd = CreateWindow(

        szWindowClass,

        szTitle,

        WS_OVERLAPPEDWINDOW,

        CW_USEDEFAULT, CW_USEDEFAULT,

        500, 100,

        NULL,

        NULL,

        hInstance,

        NULL

    );

    if (!hWnd)

    {

        MessageBox(NULL,

            _T("Call to CreateWindow failed!"),

            _T("Win32 Guided Tour"),

            NULL);

        return 1;

    }

    // The parameters to ShowWindow explained:

    // hWnd: the value returned from CreateWindow

    // nCmdShow: the fourth parameter from WinMain

    ShowWindow(hWnd,

        nCmdShow);

    UpdateWindow(hWnd);

    // Main message loop:

    MSG msg;

    while (GetMessage(&msg, NULL, 0, 0))

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }

    return (int) msg.wParam;

}

向 WndProc 添加功能

WndProc 函数的用途是处理应用程序接收的消息。通常使用 Switch 函数实现此操作。

我们将处理的第一个消息是 WM_PAINT 消息。当必须更新应用程序窗口的一部分时，应用程序会收到此消息。首次创建窗口时，必须更新整个窗口，并传递此消息以指示此操作。

当处理 WM_PAINT 消息时，首先应做的是调用 BeginPaint，最后应做的是调用 EndPaint。在这两个函数调用之间，您可以处理所有的逻辑，以在窗口中排列文本、按钮和其他控件。对于此应用程序，我们在窗口中显示字符串“Hello, World!”。若要显示文本，请使用 TextOut 函数，也可以使用drawtext函数如下所示：

PAINTSTRUCT ps;

HDC hdc;

TCHAR greeting[] = _T("Hello, World!");

switch (message)

{

case WM_PAINT:

    hdc = BeginPaint(hWnd, &ps);

    // Here your application is laid out.// For this introduction, we just print out "Hello, World!"

    // in the top left corner.TextOut(hdc,

        5, 5,

        greeting, _tcslen(greeting));

    // End application-specific layout section.EndPaint(hWnd, &ps);

    break;

}

PAINTSTRUCT ps;

HDC hdc;

TCHAR greeting[] = _T("Hello, World!");

switch (message)

{

case WM_PAINT:

    hdc = BeginPaint(hWnd, &ps);

    // Here your application is laid out.// For this introduction, we just print out "Hello, World!"

    // in the top left corner.TextOut(hdc,

        5, 5,

        greeting, _tcslen(greeting));

    // End application-specific layout section.EndPaint(hWnd, &ps);

    break;

}

应用程序通常会处理许多其他消息，如 WM_CREATE 和 WM_DESTROY。一个简单而完整的 WndProc 函数如下：
```
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)

{

    PAINTSTRUCT ps;

    HDC hdc;

    TCHAR greeting[] = _T("Hello, World!");

    switch (message)

    {

    case WM_PAINT:

        hdc = BeginPaint(hWnd, &ps);

        // Here your application is laid out.// For this introduction, we just print out "Hello, World!"

        // in the top left corner.TextOut(hdc,

            5, 5,

            greeting, _tcslen(greeting));

        // End application specific layout section.EndPaint(hWnd, &ps);

        break;

    case WM_DESTROY:

        PostQuitMessage(0);

        break;

    default:

        return DefWindowProc(hWnd, message, wParam, lParam);

        break;

    }

    return 0;

}

完整代码：
```
#include <windows.h>
#include <stdlib.h>
#include <string.h>
#include <tchar.h>

// Global variables

// The main window class name.static TCHAR szWindowClass[] = _T("win32app");

// The string that appears in the application's title bar.static TCHAR szTitle[] = _T("Win32 Guided Tour Application");

HINSTANCE hInst;

// Forward declarations of functions included in this code module:
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
WNDCLASSEX wcex;

wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = WndProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance;
wcex.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APPLICATION));
wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
wcex.lpszMenuName = NULL;
wcex.lpszClassName = szWindowClass;
wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

if (!RegisterClassEx(&wcex))
{
MessageBox(NULL,
_T("Call to RegisterClassEx failed!"),
_T("Win32 Guided Tour"),
NULL);

return 1;
}

hInst = hInstance; // Store instance handle in our global variable

// The parameters to CreateWindow explained:
// szWindowClass: the name of the application
// szTitle: the text that appears in the title bar
// WS_OVERLAPPEDWINDOW: the type of window to create
// CW_USEDEFAULT, CW_USEDEFAULT: initial position (x, y)
// 500, 100: initial size (width, length)
// NULL: the parent of this window
// NULL: this application does not have a menu bar
// hInstance: the first parameter from WinMain
// NULL: not used in this application
HWND hWnd = CreateWindow(
szWindowClass,
szTitle,
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT,
500, 100,
NULL,
NULL,
hInstance,
NULL
);

if (!hWnd)
{
MessageBox(NULL,
_T("Call to CreateWindow failed!"),
_T("Win32 Guided Tour"),
NULL);

return 1;
}

// The parameters to ShowWindow explained:
// hWnd: the value returned from CreateWindow
// nCmdShow: the fourth parameter from WinMain
ShowWindow(hWnd,
nCmdShow);
UpdateWindow(hWnd);

// Main message loop:
MSG msg;
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}

return (int) msg.wParam;
}

//
// FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
// PURPOSE: Processes messages for the main window.//
// WM_PAINT - Paint the main window
// WM_DESTROY - post a quit message and return
//
//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
TCHAR greeting[] = _T("Hello, World!");

switch (message)
{
case WM_PAINT:
hdc = BeginPaint(hWnd, &ps);

// Here your application is laid out.// For this introduction, we just print out "Hello, World!"
// in the top left corner.TextOut(hdc,
5, 5,
greeting, _tcslen(greeting));
// End application-specific layout section.EndPaint(hWnd, &ps);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
break;
}

return 0;
}