CreateDC

Creates a device context (DC) for a specified device.

Syntax

HDC CreateDC(
    LPCSTR   pwszDriver,
    LPCSTR   pwszDevice,
    LPCSTR   pwszOutput,
    const DEVMODE *pDevMode
);

Parameters

pwszDriver	Pointer to a string that specifies the name of the display driver. This is the same string that was passed to the `RegisterClass` function.
pwszDevice	Pointer to a string that specifies the device name. For most display drivers this can be `NULL` to use the default device.
pwszOutput	Pointer to a string that specifies the output port. If `NULL`, the default output is used.
pDevMode	Pointer to a `DEVMODE` structure that contains device initialization data. This parameter can be `NULL` to use the default settings.

Return Value

If the function succeeds, the return value is a handle to a device context for the specified device. If the function fails, the return value is NULL. To get extended error information, call GetLastError.

Remarks

The created DC can be used with any GDI function that requires a device context.
When you are finished with the DC, call DeleteDC to release it.
For printers, the pwszDriver is typically \\.\PRINTER and pwszDevice is the printer name.

Example

#include <windows.h>
#include <stdio.h>

int main()
{
    // Create a DC for the display driver
    HDC hdc = CreateDC("DISPLAY", NULL, NULL, NULL);
    if (hdc == NULL) {
        printf("CreateDC failed. Error: %lu\\n", GetLastError());
        return 1;
    }

    // Use the DC – draw a simple rectangle
    Rectangle(hdc, 50, 50, 200, 150);

    // Pause so the window stays visible
    system("pause");

    // Release the DC
    DeleteDC(hdc);
    return 0;
}

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