The Value Set control processes it text according to its window bidi attributes.
The VS_RIGHTTOLEFT style is used to make the Value Set control have RtL window orientation.
Each item in the Value Set can have its own bidirectional attributes. Managing the item bidi attributes is performed by the following window messages:
If no item bidi attribute is set using the VM_SETITEMBIDIATTR message the item uses the window bidi attributes.
Parameters of VM_SETITEMBIDIATTR:
mp1 - MPFROM2SHORT(usLine, usColumn)
mp2 - pointer to the following structure.
typedef struct _BD_ATTR_MASK { ULONG ulBD_Attr; ULONG ulBD_Mask; } BD_ATTR_MASK
Parameters of VM_QUERYITEMBIDIATTR:
mp1 - MPFROM2SHORT(usLine, usColumn)
mp2 - PULONG pBidiAttr - points to a ULONG where bidi attributes are returned.