Why do I get the error "TextFrame is undefined" ?

the same question was asked here 

Hi @Charu Rajput, when I refer to `TextFrame` in the example you give, I get the same error as @andyf65867865, but only if I launch the script from Illustrator—if I launch it from VSCode debugger it works fine. My sample code is:

(function () {

    var textRef = app.activeDocument.selection[0];

    if (textRef.constructor === TextFrame)
        alert('yes');
    else
        alert('no');

})();

So this code gives error if run from Illustrator, but not from VSCode debugger. Is your experience different? I am on MacOS 15.0 (AI 28.7.1).

Anyway, the idiom I use these days is almost always

if (textRef.constructor.name === 'TextFrame')

I prefer this to `typename` because I can use it with non-DOM objects, eg. Array. (Only Illustrator's objects have a `typename`.)

- Mark

var doc = app.activeDocument;
var textRef = doc.selection[0]; // assume text frame is selected 
if (textRef.constructor == TextFrame) {
    alert("It is a textframe");
}