javascript 拖动表格行实现代码

2019-11-20 23:49:48

字体：大中小

来源：转载

供稿：网友

行拖动的实现思路非常简单，选中一行，往上拖就与上面的行交换位置，往下拖就与下面的行交换位置。问题是如何得到交换行。我见过一个非常详细的教程，它会把表格里的每一行的高度与Y坐标计算出来，换言之，都时是比较e.pageX是否在[rowTop,rowBottom]区间之内。但这也带来第二个问题，有多少行就有多个这样的区间。于是解法就变成取事件源对象，然后再往上取其父对象，如果其父对象是TR元素，就取其[rowTop,rowBottom]区间....思路非常直接，同时也客观做出一个限制――不能使用代理拖动。先不谈是拖动代理还是拖动实物，光是在移动鼠标的过程要做的计算量就非常大，幸好还在IE的承受范围之内。有更好的方法吗？

人之所以先入为主，因为他就握着这么几把锁匙。如果他手上的锁匙非常多时，他在开门时就会稍微停下来，认真挑选了。因此熟悉掌握越多的原生API就越好，我们就才获取更优的选项。换一个思路，在拖动时（mousedown）保存当前行及其样式与坐标，拖动中取得鼠标所在位置上的元素，这个元素是使用一个巧妙的API取得document.elementFromPoint(x,y)。通常情况，我们取得的是TD，当然如果你在里面塞进一个DIV，那就是DIV罗。然后我们再取得其TR元素，然后比较mousedown时保存的TR元素是不是同一个元素，不是同一个元素，我们才做进一步的操作。这时我们就要判其是向上移向下移，简单的减法而已。接着是交换两行，使用insertBefore。最后当mouseup时，还原行的样式就是！由于没有复杂的坐标计算，整个程式出奇的高效！

完整演示代码

<!doctype html><html> <head>  <title>表格行拖动</title>  <script>     window.onload = function(){    //绑定事件    var addEvent = document.addEventListener ? function(el,type,callback){     el.addEventListener( type, callback, !1 );    } : function(el,type,callback){     el.attachEvent( "on" + type, callback );    }    //移除事件    var removeEvent = document.removeEventListener ? function(el,type,callback){     el.removeEventListener( type, callback );    } : function(el,type,callback){     el.detachEvent( "on" + type, callback);    }    //精确获取样式    var getStyle = document.defaultView ? function(el,style){     return document.defaultView.getComputedStyle(el, null).getPropertyValue(style)    } : function(el,style){     style = style.replace(//-(/w)/g, function($, $1){      return $1.toUpperCase();     });     return el.currentStyle[style];    }    var dragManager = {     clientY:0,     draging:function(e){//mousemove时拖动行      var dragObj = dragManager.dragObj;      if(dragObj){       e = e || event;       if(window.getSelection){//w3c        window.getSelection().removeAllRanges();       }else if(document.selection){        document.selection.empty();//IE       }       var y = e.clientY;       var down = y > dragManager.clientY;//是否向下移动       var tr = document.elementFromPoint(e.clientX,e.clientY);       if(tr && tr.nodeName == "TD"){        tr = tr.parentNode        dragManager.clientY = y;        if( dragObj !== tr){         tr.parentNode.insertBefore(dragObj, (down ? tr.nextSibling : tr));        }       };      }     },     dragStart:function(e){      e = e || event;      var target = e.target || e.srcElement;      if(target.nodeName === "TD"){       target = target.parentNode;       dragManager.dragObj = target;       if(!target.getAttribute("data-background")){        var background = getStyle(target,"background-color");        target.setAttribute("data-background",background)       }       //显示为可移动的状态       target.style.backgroundColor = "#ccc";       target.style.cursor = "move";       dragManager.clientY = e.clientY;       addEvent(document,"mousemove",dragManager.draging);       addEvent(document,"mouseup",dragManager.dragEnd);      }     },     dragEnd:function(e){      var dragObj = dragManager.dragObj      if (dragObj) {       e = e || event;       var target = e.target || e.srcElement;       if(target.nodeName === "TD"){        target = target.parentNode;        dragObj.style.backgroundColor = dragObj.getAttribute("data-background");        dragObj.style.cursor = "default";        dragManager.dragObj = null;        removeEvent(document,"mousemove",dragManager.draging);        removeEvent(document,"mouseup",dragManager.dragEnd);       }      }     },     main:function(el){      addEvent(el,"mousedown",dragManager.dragStart);     }    }    var el = document.getElementById("table");    dragManager.main(el);   }     </script>  <style>   .table{    width:60%;    border: 1px solid red;    border-collapse: collapse;   }   .table td{    border: 1px solid red;    height: 20px;   }  </style> </head> <body>  <h1>表格行拖动</h1>  <table id="table" class="table">   <tbody>    <tr>     <td>1</td>     <td>One</td>     <td>dom.require</td>    </tr>    <tr id="2" >     <td class="2">2</td>     <td>Two</td>     <td>ControlJS </td>    </tr>    <tr id="3" >     <td class="3">3</td>     <td>Three</td>     <td>HeadJS</td>    </tr>    <tr id="4" >     <td class="4">4</td>     <td>Four</td>     <td>LAB.js</td>    </tr>    <tr id="5" >     <td class="5">5</td>     <td>Five</td>     <td>$script.js</td>    </tr>    <tr id="6" >     <td class="6">6</td>     <td>Six</td>     <td>NBL.js</td>    </tr>   </tbody>  </table> </body></html>

核心代码

 window.onload = function(){ //绑定事件 var addEvent = document.addEventListener ? function(el,type,callback){  el.addEventListener( type, callback, !1 ); } : function(el,type,callback){  el.attachEvent( "on" + type, callback ); } //移除事件 var removeEvent = document.removeEventListener ? function(el,type,callback){  el.removeEventListener( type, callback ); } : function(el,type,callback){  el.detachEvent( "on" + type, callback); } //精确获取样式 var getStyle = document.defaultView ? function(el,style){  return document.defaultView.getComputedStyle(el, null).getPropertyValue(style) } : function(el,style){  style = style.replace(//-(/w)/g, function($, $1){   return $1.toUpperCase();  });  return el.currentStyle[style]; } var dragManager = {  clientY:0,  draging:function(e){//mousemove时拖动行   var dragObj = dragManager.dragObj;   if(dragObj){    e = e || event;//清除选区    if(window.getSelection){//w3c     window.getSelection().removeAllRanges();    }else if(document.selection){     document.selection.empty();//IE    }    var y = e.clientY;    var down = y > dragManager.clientY;//是否向下移动    var tr = document.elementFromPoint(e.clientX,e.clientY);    if(tr && tr.nodeName == "TD"){     tr = tr.parentNode     dragManager.clientY = y;     if( dragObj !== tr){      tr.parentNode.insertBefore(dragObj, (down ? tr.nextSibling : tr));     }    };   }  },  dragStart:function(e){   e = e || event;   var target = e.target || e.srcElement;   if(target.nodeName === "TD"){    target = target.parentNode;    dragManager.dragObj = target;    if(!target.getAttribute("data-background")){     var background = getStyle(target,"background-color");     target.setAttribute("data-background",background)    }    //显示为可移动的状态    target.style.backgroundColor = "#ccc";    target.style.cursor = "move";    dragManager.clientY = e.clientY;    addEvent(document,"mousemove",dragManager.draging);    addEvent(document,"mouseup",dragManager.dragEnd);   }  },  dragEnd:function(e){   var dragObj = dragManager.dragObj   if (dragObj) {    e = e || event;    var target = e.target || e.srcElement;    if(target.nodeName === "TD"){     target = target.parentNode;     dragObj.style.backgroundColor = dragObj.getAttribute("data-background");     dragObj.style.cursor = "default";     dragManager.dragObj = null;     removeEvent(document,"mousemove",dragManager.draging);     removeEvent(document,"mouseup",dragManager.dragEnd);    }   }  },  main:function(el){   addEvent(el,"mousedown",dragManager.dragStart);  } } var el = document.getElementById("table"); dragManager.main(el);}

实现代码二

<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml" > <head > <title>无标题页</title> </head> <body> <table id="tb1" border="1" cellpadding="3"> <tr> <th>移动</th> <th>数据</th> <th>数据</th> <th>数据</th> </tr> <tr> <td>*</td> <td>11111111111</td> <td>sdgergserhserhserh</td> <td>awegaw</td> </tr> <tr> <td>*</td> <td>222222222</td> <td>serherwwwwww</td> <td>fafafff</td> </tr> <tr> <td>*</td> <td>333333333</td> <td>qqqqqqqwewer</td> <td>yukyuk</td> </tr> </table> <script type="text/javascript"> var curTr = null; var tb1 = document.getElementById('tb1'); var trs = tb1.getElementsByTagName('tr'); tb1.onselectstart = function(){ if(curTr){ document.selection.empty(); return true; } }; for(var i=1; i<trs.length; i++) { var tds = trs[i].getElementsByTagName('td'); tds[0].style.cursor = 'move'; tds[0].onmousedown = function(){ curTr = this.parentNode; curTr.style.backgroundColor = '#eff'; }; tds[0].onmouseover = function() { if(curTr && curTr != this.parentNode) { this.parentNode.swapNode(curTr); } } } document.body.onmouseup = function(){ if(curTr){ curTr.style.backgroundColor = ''; curTr = null; } }; </script> </body> </html>

注：不兼容firefox，在IE和chrome下测试通过哦。

上一篇：jQuery bind事件使用详解

下一篇：精心收集的jQuery常用的插件1000