LoadCursor

LoadCursor is a function in the Windows API that is used to load a cursor resource from an executable file or a system-defined cursor. Cursors are graphical images that represent the mouse pointer on the screen. When you move the mouse, the operating system moves the cursor accordingly. LoadCursor is a crucial function for customizing the user interface of Windows applications by allowing developers to specify different cursor designs for various user interactions.

The function takes two parameters: the instance handle of the module containing the cursor resource and the resource identifier of the cursor. The instance handle is typically obtained using GetModuleHandle, and the resource identifier can be a string name or an integer ID. If the function successfully loads the cursor, it returns a handle to the cursor. Otherwise, it returns NULL.

Windows provides a set of predefined cursors that can be loaded using LoadCursor with the hmodule parameter set to NULL and the lpCursorName parameter set to one of the system-defined cursor identifiers, such as IDC_ARROW, IDC_IBEAM, or IDC_WAIT. These identifiers are defined in the `windows.h` header file. Applications can also define their own custom cursor resources within their executable files or in separate resource files. These custom cursors can then be loaded using LoadCursor with the application's instance handle.

Once a cursor handle is obtained, it can be set as the current mouse cursor for a window using the SetCursor function. This allows the application to change the appearance of the mouse pointer dynamically, for example, to indicate that a drag operation is in progress or that the system is busy.