The pragma affects how the result of converting an enumeration component with the
TO_STRING operator is output. If the enumeration declaration has the pragma, then the name
of the enumeration component appears as a string instead of the numeric value.
Syntax:
{attribute 'to_string'}
Insert location: First line above the declaration part of the enumeration.
Example
Declaration of the enumeration color:
{attribute 'to_string'}
TYPE color :
(
red := 0,
blue := 1,
green := 2
);
END_TYPE
Conversion with TO_STRING:
PROGRAM PLC_PRG VAR i_color: Color; s_show_color: STRING; END_VAR i_color := 1; s_show_color := TO_STRING(i_color);
In this case, str_show_color gets the value 'blue' instead of '1' as the conversion result.
See also