ID Number: Q75865
3.00
WINDOWS
Summary:
SYMPTOMS
When the WM_SETTEXT message is used to place text into an edit
control, more text than the text length limit specified in an
EM_LIMITTEXT message can be placed into the control.
RESOLUTION
This is the designed behavior for these messages. This allows an
application to create an edit control where only the first "n"
characters can be entered by the user, and the remainder of the
text is specified by the application ("n" is specified in the
EM_LIMITTEXT message).
More Information:
There is a limitation to this method. If the application specifies more
text than is specified in the EM_LIMITTEXT message, the user can edit
the entire contents of the edit control.
There are two ways to work around this limitation:
1. Erase all text from the edit control before allowing the user to
enter text.
2. After each WM_SETTEXT message, truncate the edit control text to
less than the limit specified in the EM_LIMITTEXT message.
The edit control will enforce the length limit if the amount of text
in the control is less than the limit. Using a WM_SETTEXT message
allows the application to violate the limit.