Feature Detection for setDragImage of HTML5 Drag and Drop

Question

Is there a way to do feature detection for setDragImage of HTML5 Drag and Drop (in JavaScript or Dart)?

I do the general HTML5 Drag and Drop feature detection with the following (from guide to detecting everything):

return 'draggable' in document.createElement('span');

This will return true for Chrome, Firefox, etc., and IE10. It will return false for IE9.

Now, the problem is with IE10: While it supports most of HTML5 Drag and Drop, setDragImage is not supported and I need to provide a polyfill just for setDragImage. But I couldn't figure out a way how to detect this.

Answer 1

This solution assumes general D&D support has already been checked.

JavaScript (tested in IE, Firefox, Opera and Chrome):

function test() {
    var testVar = window.DataTransfer || window.Clipboard;  // Clipboard is for Chrome
    if("setDragImage" in testVar.prototype) {
        window.alert("supported");
    } else {
        window.alert("not supported");
    }
}

Dart:

I didn't find a way to do this with "native" Dart code, so js-interop is the way to go.