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Drag and Drop HTML5 not working?

I am trying to understand the drag and drop for html5, I can get it to drag and have the element that is suppose to take the dragged element accept it. However I cant get the ondrag or ondragenter, or at least the functions those events call to work I'm not really sure what I'm doing wrong.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Week 3 Drag and Drop</title>
<link rel="stylesheet" type="text/css" href="Week3DragAndDropCSS.css">
<script src="Week3DragAndDropJS.js"></script>
</head>
<body>
<header>
    <h1>Week 3 Drag and Drop</h1>
</header>

<div style="height:200px;width:200px;background: red"    
    id="obj1"draggable="true"></div>
<div style="height:200px;width:200px;background:
    green"id="obj2"draggable="true"></div>
<div style="height:200px;width:200px;background: orange" 
    id="obj3"draggable="true"></div>    
<div style="height:200px;width:200px;background-image: url
    ('trash.png');background-repeat: no-repeat;" id="trashCan" 
    ondragover="allowDrop(event)" ondragenter="setBorder(event,'5px')" 
    ondragleave="setBorder(event,'2px')" ondrop="drop(event)"></div>




<footer>

</footer>

    </body>

    </html>

Then here is my js:

function drag(evt){
evt.dataTransfer.setData("color", ev.target.background);
}
function allowDrop(evt){
evt.preventDefault();
}
function drop(evt){
evt.preventDefault();
var color = evt.dataTransfer.getData("color");
evt.currentTarget.style.background = color; 

}
function setBorder(evt,size){
evt.currentTarget.border = (size +"solid black");
}

Try to fix errors first.

function drop(evt){ // define parameter evt
    ...
}
function setBorder(evt,size){
    evt.currentTarget.border = (size + "solid black"); // use + to concat
}

Here is what I have written from a past tutorial I went through (it was probably similar to the one you're doing to learning about this):

function drop(evt)
{
  evt.preventDefault();
  var data = evt.dataTransfer.getData("text");
  evt.target.appendChild(document.getElementById(data));
}

What I believe is missing from your drop function is a call to appendChild(), which would what be what actually "drags" the element from one place to another (in addition to syntactic errors that were pointed out in a previous answer).

minor syntax mistakes reffer following fiddle

 function drag(evt){ evt.dataTransfer.setData("color", evt.target.style.backgroundColor); } function allowDrop(evt){ evt.preventDefault(); } function drop(evt){ evt.preventDefault(); var color = evt.dataTransfer.getData("color"); evt.currentTarget.style.background = color; } function setBorder(evt,size){ evt.currentTarget.style.border = (size +" solid black"); } 
 <body> <header> <h1>Week 3 Drag and Drop</h1> </header> <div style="height:200px;width:200px;background: red" id="obj1"draggable="true" ondragstart="drag(event)"></div> <div style="height:200px;width:200px;background: green"id="obj2"draggable="true" ondragstart="drag(event)"></div> <div style="height:200px;width:200px;background: orange" id="obj3"draggable="true" ondragstart="drag(event)"></div> <div style="height:200px;width:200px;background-image: url ('trash.png');background-repeat: no-repeat;" id="trashCan" ondragover="allowDrop(event)" ondragenter="setBorder(event,'5px')" ondragleave="setBorder(event,'2px')" ondrop="drop(event)"></div> <footer> </footer> </body> 

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