EM_LIMITTEXT
An
application sends an EM_LIMITTEXT message to limit the amount of text the user
may enter into an edit control.
EM_LIMITTEXT
wParam = (WPARAM) cchMax; // text length, in characters
lParam = 0; // not used; must be zero
Parameters
cchMax
Value of wParam.
Specifies the maximum number of characters the user can enter. If this
parameter is zero, the text length is set to 0x7FFFFFFE characters for
single-line edit controls or 0xFFFFFFFF for multiline edit controls.
Return Values
This message
does not return a value.
Remarks
The
EM_LIMITTEXT message limits only the text the user can enter. It has no effect
on any text already in the edit control when the message is sent, nor does it
affect the length of the text copied to the edit control by the WM_SETTEXT
message. If an application uses the WM_SETTEXT message to place more text into
an edit control than is specified in the EM_LIMITTEXT message, the user can
edit the entire contents of the edit control.
The default
limit to the amount of text a user can enter in an edit control is 30,000
characters.
In a rich
edit control, use the message EM_EXLIMITTEXT for text length values greater
than 64K.
See Also