INFO: How Keyboard Data Is Translated

SUMMARY

Keyboard input is acquired by the keyboard driver, which in turn produces a scan code. This scan code is passed on to the locale-specific Win32 subsystem keyboard driver. This locale-specific driver then converts the scan code to a virtual key and a Unicode character. The Win32 subsystem then passes on this information to the application.

All messages in the Win32 application programming interface (API) that present textual information to a window procedure depend upon how the window registered its class. For example, if RegisterClassW() was called, then Unicode is presented; if RegisterClassA() was called, then ANSI is presented. The conversion of the text is handled by the Window Manager. This allows an ANSI application to send textual information to a Unicode application.