Fire Dragstart and drop manually

drag-and-drop.js

var dragDataTransfer = {
   data: {},
   setData: function(type, value) { this.data[type] = value; },
   getData: function(type) { return this.data[type] }
};

function getDragDropEvent(type, dataTransfer) {
   var dragDropEvent = new DragEvent(type);
   console.log('xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx', dataTransfer);
   Object.defineProperty(dragDropEvent.constructor.prototype, 'dataTransfer', dataTransfer);
   console.log('xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx',  dragDropEvent.dataTransfer.getData('Text'));
   return dragDropEvent;
}

dragDataTransfer.setData('Text', 'foo....................');
var dragstaEv = getDragDropEvent('dragstart', dragDataTransfer);
document.querySelector('#draggable').dispatchEvent(dragstaEv);
//
// var dropEV = getDragEvent('drop', dragDataTransfer);
// document.querySelector('#draggable').dispatchEvent(dropEv);
// console.log('............', dragstaEv.dataTransfer.getData('Text');