通过Java拖放类（HTML5）

Question

我在https://stackoverflow.com/questions/34382935/drag-and-drop-anywhere-on-screen-with-multiple-elements-of-the-same-id-class-and#上跟踪此问题=

现在，我正在使用这个有效的解决方案，以解决由robertc在上面为该stackoverflow问题创建的jsfiddle上的一个备用元素： HTML5：dragover（），drop（）：如何获取当前的x，y坐标？

这是当前的代码：（记入robertc）

 function drag_start(event) { var style = window.getComputedStyle(event.target, null); event.dataTransfer.setData("text", (parseInt(style.getPropertyValue("left"),10) - event.clientX) + ',' + (parseInt(style.getPropertyValue("top"),10) - event.clientY)); } function drag_over(event) { event.preventDefault(); return false; } function drop(event) { var offset = event.dataTransfer.getData("text").split(','); var dm = document.getElementById('dragme'); dm.style.left = (event.clientX + parseInt(offset[0],10)) + 'px'; dm.style.top = (event.clientY + parseInt(offset[1],10)) + 'px'; event.preventDefault(); return false; } var dm = document.getElementById('dragme'); dm.addEventListener('dragstart',drag_start,false); document.body.addEventListener('dragover',drag_over,false); document.body.addEventListener('drop',drop,false); 

 aside { position: absolute; left: 0; top: 0; /* set these so Chrome doesn't return 'auto' from getComputedStyle */ width: 200px; background: rgba(255,255,255,0.66); border: 2px solid rgba(0,0,0,0.5); border-radius: 4px; padding: 8px; } 

 <aside draggable="true" id="dragme"> This is an aside, drag me. </aside> <p>I never am really satisfied that I understand anything; because, understand it well as I may, my comprehension can only be an infinitesimal fraction of all I want to understand about the many connections and relations which occur to me, how the matter in question was first thought of or arrived at, etc., etc.</p> <p>In almost every computation a great variety of arrangements for the succession of the processes is possible, and various considerations must influence the selections amongst them for the purposes of a calculating engine. One essential object is to choose that arrangement which shall tend to reduce to a minimum the time necessary for completing the calculation.</p> <p>Many persons who are not conversant with mathematical studies imagine that because the business of [Babbage's Analytical Engine] is to give its results in numerical notation, the nature of its processes must consequently be arithmetical and numerical, rather than algebraical and analytical. This is an error. The engine can arrange and combine its numerical quantities exactly as if they were letters or any other general symbols; and in fact it might bring out its results in algebraical notation, were provisions made accordingly.</p> <p>The Analytical Engine has no pretensions whatever to originate anything. It can do whatever we know how to order it to perform. It can follow analysis, but it has no power of anticipating any analytical revelations or truths. Its province is to assist us in making available what we are already acquainted with.</p> 

它对于唯一ID的单个元素非常有效。 但是，我正在尝试使其可用于同一类的多个元素（分别拖动）。 我尝试了很多次，但都无济于事，我也找不到解决方案。

想知道是否有任何HTML / Javascript专家可以提供帮助？ 谢谢！

Answer 1

我对您的问题的理解是，您希望页面上可以有多个可拖动对象。

归功于@Ingvi用户，答案位于此处 。 用户的原始PEN位于此处 。

 function drag_start(event) { var style = window.getComputedStyle(event.target, null); event.dataTransfer.setData("text/plain", (parseInt(style.getPropertyValue("left"), 10) - event.clientX) + ',' + (parseInt(style.getPropertyValue("top"), 10) - event.clientY) + ',' + event.target.getAttribute('data-item')); } function drag_over(event) { event.preventDefault(); return false; } function drop(event) { var offset = event.dataTransfer.getData("text/plain").split(','); var dm = document.getElementsByClassName('dragme'); dm[parseInt(offset[2])].style.left = (event.clientX + parseInt(offset[0], 10)) + 'px'; dm[parseInt(offset[2])].style.top = (event.clientY + parseInt(offset[1], 10)) + 'px'; event.preventDefault(); return false; } var dm = document.getElementsByClassName('dragme'); for (var i = 0; i < dm.length; i++) { dm[i].addEventListener('dragstart', drag_start, false); document.body.addEventListener('dragover', drag_over, false); document.body.addEventListener('drop', drop, false); } 

 aside { position: absolute; left: 0; top: 0; /* set these so Chrome doesn't return 'auto' from getComputedStyle */ width: 200px; background: rgba(255, 255, 255, 0.66); border: 2px solid rgba(0, 0, 0, 0.5); border-radius: 4px; padding: 8px; } 

 <aside draggable="true" class="dragme" data-item="0">One</aside> <aside draggable="true" class="dragme second" data-item="1">Two</aside> <p>I never am really satisfied that I understand anything; because, understand it well as I may, my comprehension can only be an infinitesimal fraction of all I want to understand about the many connections and relations which occur to me, how the matter in question was first thought of or arrived at, etc., etc.</p> <p>In almost every computation a great variety of arrangements for the succession of the processes is possible, and various considerations must influence the selections amongst them for the purposes of a calculating engine. One essential object is to choose that arrangement which shall tend to reduce to a minimum the time necessary for completing the calculation.</p> <p>Many persons who are not conversant with mathematical studies imagine that because the business of [Babbage's Analytical Engine] is to give its results in numerical notation, the nature of its processes must consequently be arithmetical and numerical, rather than algebraical and analytical. This is an error. The engine can arrange and combine its numerical quantities exactly as if they were letters or any other general symbols; and in fact it might bring out its results in algebraical notation, were provisions made accordingly.</p> <p>The Analytical Engine has no pretensions whatever to originate anything. It can do whatever we know how to order it to perform. It can follow analysis, but it has no power of anticipating any analytical revelations or truths. Its province is to assist us in making available what we are already acquainted with.</p>