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The framework calls this member function when a key is pressed. That is, the current window has the keyboard focus and a WM_KEYDOWN message is translated by the TranslateMessage function.

afx_msg void OnUniChar(
    UINT nChar, 
    UINT nRepCnt, 
    UINT nFlags



[in] nChar

Specifies the character code of the pressed key.

[in] nRepCnt

Specifies the repeat count for the current message. The value is the number of times the keystroke is autorepeated as a result of the user holding down the key. If the keystroke is held long enough, multiple messages are sent. However, the repeat count is not cumulative.

[in] nFlags

Flags that specify the scan code, extended key, context code, previous key state, and transition state, as shown in the following table:




Specifies the scan code. The value depends on the original equipment manufacturer (OEM).


Specifies an extended key, such as the right-hand ALT and CTRL keys that appear on an enhanced 101 or 102-key keyboard. The flag is 1 if the key is an extended key; otherwise, it is 0.


Used internally by Windows.


Specifies the context code. The flag is 1 if the ALT key is held down while the key is pressed; otherwise, the value is 0.


Specifies the previous key state. The flag is 1 if the key is down before the message is sent, or 0 if the key is up.


Specifies the transition state. The flag is 1 if the key is being released, or 0 if the key is being pressed.

This method receives the WM_UNICHAR notification, which is described in the Windows SDK. The WM_UNICHAR message is designed to send or post Unicode characters to ANSI windows. It is equivalent to the WM_CHAR message, but uses Unicode Transformation Format-32 encoding (UTF-32), whereas the WM_CHAR message uses UTF-16.


This member function is called by the framework to allow your application to handle a Windows message. The parameters passed to your function reflect the parameters received by the framework when the message was received. If you call the base-class implementation of this function, that implementation will use the parameters originally passed with the message and not the parameters you supply to the function.

Header: afxwin.h

This method is supported in Windows Vista and later.

Additional requirements for this method are described in Build Requirements for Windows Vista Common Controls.