IsWindowUnicode function (winuser.h)

Determines whether the specified window is a native Unicode window.

BOOL IsWindowUnicode(
  [in] HWND hWnd
);

[in] hWnd

Type: HWND

A handle to the window to be tested.

Type: BOOL

If the window is a native Unicode window, the return value is nonzero.

If the window is not a native Unicode window, the return value is zero. The window is a native ANSI window.

The character set of a window is determined by the use of the RegisterClass function. If the window class was registered with the ANSI version of RegisterClass (RegisterClassA), the character set of the window is ANSI. If the window class was registered with the Unicode version of RegisterClass (RegisterClassW), the character set of the window is Unicode.

The system does automatic two-way translation (Unicode to ANSI) for window messages. For example, if an ANSI window message is sent to a window that uses the Unicode character set, the system translates that message into a Unicode message before calling the window procedure. The system calls IsWindowUnicode to determine whether to translate the message.

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