chrome 中的 event.dataTransfer.dropEffect

Question

I have a script which determines the result of drag and drop operation from the value of event.dataTransfer.dropEffect. I set the property event.dataTransfer.effectAllowed to value "copymove". In Firefox the value of dropEffect is "move" by default and "copy" when I press ctrl key during drag. In Chrome, the value of dropEffect is always "none". Does Chrome not suppot this API?

Answer 1

This is a bug in Chrome (and in Internet Explorer). For Chrome there is a bug report: https://bugs.chromium.org/p/chromium/issues/detail?id=39399

As a solution you must store the content of dropEffect in a global variable while the drag events and use its content instead of event.dataTransfer.dropEffect if that value is "none" in the drop event.