How do I get the string representation if I know the enum of integer value ?
type
MyEnum = (tmp_one, tmp_two, tmp_three);
const
MyTypeNames: array[tmp_one..tmp_three] of string = ('One', 'Two', 'Three');
3 Answers
I'm assuming that you have an ordinal value rather than a variable of this enumerated type. If so then you just need to cast the ordinal to the enumerated type. Like this:
function GetNameFromOrdinal(Ordinal: Integer): string;
begin
Result := MyTypeNames[MyEnum(Ordinal)];
end;
answered Oct 16, 2012 at 14:47
David Heffernan
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4 Comments
Andreas Rejbrand
IMHO it is a bit overkill with a function. But of course you could argue that it is for illustrative purposes.
Ken White
Why not just pass in a
MyEnum parameter and avoid the typecast? The types are hard-coded already.Andreas Rejbrand
@Ken: I believe David took notice of the 'if I know the enum of integer value' part of the question.
David Heffernan
@Andreas I made it a function because that's just an easy way to be explicit about the types of parameter and return value
I assume you want to use the names in your array of string. Then this is very simple:
var
myEnumVar: MyEnum;
begin
myEnumVar := tmp_two; // For example
ShowMessage(MyTypeNames[myEnumVar]);
Comments
You don't need to use the ordinal values of your enum type. You can declare an array with the enum type as its "subscript" and use an enum var directly.
type
TMyEnum = (tmp_one, tmp_two, tmp_three);
const
MyTypeNames: array[TMyEnum] of string = ('One', 'Two', 'Three');
function Enum2Text(aEnum: TMyEnum): string;
begin
Result := MyTypeNames[aEnum];
end;
Call it with the enum or an integer value cast to the enum:
Enum2Text(tmp_one); // -> 'One'
Enum2Text(TMyEnum(2)); // -> 'Three'
T, likeTMyEnum. Also, the members of the enum should be likemeOne, meTwo, meThree. [Compare:TFontStyle = (fsBold, fsItalic, fsUnderline, fsStrikeOut); TWindowState = (wsNormal, wsMinimized, wsMaximized)etc.]