BCGControlBar Pro for MFC
void CBCGPEditCtrl::EnableUndoCharMode ( BOOL  bEnable = TRUE)

Enables or disables undo "char mode".

Use this function to enable or disable undo "char mode". When "char mode" is enabled each character is stored in the undo buffer separately. When "char mode" is disabled only full words (sets of characters delimited by any of delimiters from m_strWordDelimeters) are stored in the undo buffer.

bEnableIf TRUE undo "char mode" will be enabled; otherwise undo "char mode" will be disabled.