win32 api绘制按钮，绘制文字。用户点击此按钮，在窗口中重绘其它新的文字

要绘制按钮和文字，可以使用Win32 API中的CreateWindowEx和DrawText函数。CreateWindowEx用于创建按钮，DrawText用于绘制文本。

以下是一个简单的示例程序，可以创建一个按钮和一个静态文本框。当用户点击按钮时，程序会在文本框中显示新的文本。

#include <windows.h>

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    WNDCLASSEX wc;
    HWND hwnd;
    MSG Msg;

    // Step 1: Registering the Window Class
    wc.cbSize = sizeof(WNDCLASSEX);
    wc.style = 0;
    wc.lpfnWndProc = WndProc;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    wc.hInstance = hInstance;
    wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
    wc.lpszMenuName = NULL;
    wc.lpszClassName = "MyClass";
    wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION);

    if (!RegisterClassEx(&wc))
    {
        MessageBox(NULL, "Window Registration Failed!", "Error!", MB_ICONEXCLAMATION | MB_OK);
        return 0;
    }

    // Step 2: Creating the Window
    hwnd = CreateWindowEx(
        WS_EX_CLIENTEDGE,
        "MyClass",
        "The Title of My Window",
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT, 240, 120,
        NULL, NULL, hInstance, NULL);

    if (hwnd == NULL)
    {
        MessageBox(NULL, "Window Creation Failed!", "Error!", MB_ICONEXCLAMATION | MB_OK);
        return 0;
    }

    // Step 3: Show the Window
    ShowWindow(hwnd, nCmdShow);
    UpdateWindow(hwnd);

    // Step 4: The Message Loop
    while (GetMessage(&Msg, NULL, 0, 0) > 0)
    {
        TranslateMessage(&Msg);
        DispatchMessage(&Msg);
    }
    return Msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    switch (msg)
    {
    case WM_CREATE:
        // Create a button
        CreateWindow(
            "BUTTON",
            "Click me!",
            WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,
            10, 10, 100, 30,
            hwnd,
            (HMENU)1,
            NULL,
            NULL);

        // Create a static text box
        CreateWindow(
            "STATIC",
            "Hello, World!",
            WS_VISIBLE | WS_CHILD,
            10, 50, 200, 30,
            hwnd,
            (HMENU)2,
            NULL,
            NULL);
        break;

    case WM_COMMAND:
        if (LOWORD(wParam) == 1) // Button clicked
        {
            // Get the handle to the static text box
            HWND hStatic = GetDlgItem(hwnd, 2);

            // Change the text in the static text box
            SetWindowText(hStatic, "Button clicked!");
        }
        break;

    case WM_PAINT:
        {
            PAINTSTRUCT ps;
            HDC hdc = BeginPaint(hwnd, &ps);
            // TODO: Add any drawing code here...
            EndPaint(hwnd, &ps);
        }
        break;

    case WM_DESTROY:
        PostQuitMessage(0);
        break;

    default:
        return DefWindowProc(hwnd, msg, wParam, lParam);
    }
    return 0;
}

在上面的示例程序中，我们在WM_CREATE消息处理程序中创建了一个按钮和一个静态文本框。当用户点击按钮时，我们在WM_COMMAND消息处理程序中获取静态文本框的句柄，并使用SetWindowText函数更改其文本内容。

要重新绘制窗口中的文本，可以在WM_PAINT消息处理程序中使用DrawText函数。您可以在此处添加绘制文本的代码。在绘制完文本后，使用EndPaint函数结束绘制过程。