EM_SETBIDIOPTIONS Message

The EM_SETBIDIOPTIONS message sets the current state of the bidirectional options in the rich edit control.

Syntax

To send this message, call the SendMessage function as follows.


lResult = SendMessage(
    // returns LRESULT in lResult
   (HWND) hWndControl,
    // handle to destination control
   (UINT) EM_SETBIDIOPTIONS,
    // message ID
   (WPARAM) wParam,
    // = (WPARAM) () wParam;
   (LPARAM) lParam
    // = (LPARAM) () lParam;

);

Parameters

wParam
This parameter is not used; it must be zero.
lParam
Pointer to a BIDIOPTIONS structure that indicates how to set the state of the bidirectional options in the rich edit control.

Return Value

This message does not return a value.

Remarks

The rich edit control must be in plain text mode or EM_SETBIDIOPTIONS will not do anything.
In plain text controls, EM_SETBIDIOPTIONS automatically determines the paragraph direction and/or alignment based on the context rules. These rules state that the direction and/or alignment is derived from the first strong character in the control. A strong character is one from which text direction can be determined (see Unicode Standard version 2.0). The paragraph direction and/or alignment is applied to the default format.
EM_SETBIDIOPTIONS only switches the default paragraph format to RTL (right to left) if it finds an RTL character,

Message Information

Header Declared in Richedit.h
Minimum operating systems Windows 95 (Middle Eastern) with Rich Edit 3.0, Windows NT 4.0 (Middle Eastern) with Rich Edit 3.0, Windows Millennium Edition (Middle Eastern), Windows 2000 (Middle Eastern)