JavaScript简单实现鼠标拖动选择功能(2)

var _selectedRegions = [];
 function RegionSelect(selRegionProp){
   this.regions =[];
   var _regions = document.getElementsBySelector(selRegionProp["region"]);
   if(_regions  &&  _regions.length > 0){
    var _self = this;
     for(var i=0; i< _regions.length;i++){
       _regions[i].onmousedown = function(){
         var evt = window.event || arguments[0];
         if(!evt.shiftKey  &&  !evt.ctrlKey){
          // 清空所有select样式
          _self.clearSelections(_regions);
          this.className += " "+_self.selectedClass;
          // 清空selected数组，并加入当前select中的元素
          _selectedRegions = [];
          _selectedRegions.push(this);
         }else{
          if(this.className.indexOf(_self.selectedClass) == -1){
            this.className += " "+_self.selectedClass;
            _selectedRegions.push(this);
          }else{
            this.className = this.className.replaceAll(_self.selectedClass,"");
            _selectedRegions.remove(this);
          }
         }
         clearEventBubble(evt);
       }
       this.regions.push(_regions[i]);
     }
   }
   this.selectedClass = selRegionProp["selectedClass"];
   this.selectedRegion = [];
   this.selectDiv = null;
   this.startX = null;
   this.startY = null;
 }

 RegionSelect.prototype.select = function(){
  var _self = this;
  addEvent("mousedown",function(){
    var evt = window.event || arguments[0];
    _self.onBeforeSelect(evt);
    clearEventBubble(evt);
  },document);

  addEvent("mousemove",function(){
    var evt = window.event || arguments[0];
    _self.onSelect(evt);
    clearEventBubble(evt);
  },document);

  addEvent("mouseup",function(){
    _self.onEnd();
  },document);
 }

 RegionSelect.prototype.onBeforeSelect = function(evt){
  if(!document.getElementById("selContainer")){
     this.selectDiv = document.createElement("div");
     this.selectDiv.style.cssText = "position:absolute;width:0px;height:0px;font-size:0px;margin:0px;padding:0px;border:1px dashed #0099FF;background-color:#C3D5ED;z-index:1000;filter:alpha(opacity:60);opacity:0.6;display:none;";
     this.selectDiv.id = "selContainer";
     document.body.appendChild(this.selectDiv);
   }else{
     this.selectDiv = document.getElementById("selContainer");
   }

   this.startX = posXY(evt).x;
   this.startY = posXY(evt).y;
   this.isSelect = true;

 }

 RegionSelect.prototype.onSelect = function(evt){
    var _self = this;
    if(_self.isSelect){
      if(_self.selectDiv.style.display == "none") _self.selectDiv.style.display = "";

      var posX = posXY(evt).x;
      var poxY = posXY(evt).y;

      _self.selectDiv.style.left   = Math.min(posX, this.startX);
     _self.selectDiv.style.top    = Math.min(poxY, this.startY);
     _self.selectDiv.style.width  = Math.abs(posX - this.startX);
     _self.selectDiv.style.height = Math.abs(poxY - this.startY); 

     var regionList = _self.regions;
     for(var i=0; i< regionList.length; i++){
       var r = regionList[i], sr = _self.innerRegion(_self.selectDiv,r);
       if(sr  &&  r.className.indexOf(_self.selectedClass) == -1){
          r.className = r.className + " "+_self.selectedClass;
          _selectedRegions.push(r);
       }else if(!sr  &&  r.className.indexOf(_self.selectedClass) != -1){
          r.className = r.className.replaceAll(_self.selectedClass,"");
         _selectedRegions.remove(r);
        }

     }
   }
 }

 RegionSelect.prototype.onEnd = function(){
  if(this.selectDiv){
    this.selectDiv.style.display = "none";
  }
  this.isSelect = false;
  //_selectedRegions = this.selectedRegion;
 }

 // 判断一个区域是否在选择区内
 RegionSelect.prototype.innerRegion = function(selDiv, region){
   var s_top = parseInt(selDiv.style.top);
   var s_left = parseInt(selDiv.style.left);
   var s_right = s_left + parseInt(selDiv.offsetWidth);
   var s_bottom = s_top + parseInt(selDiv.offsetHeight);

   var r_top = parseInt(region.offsetTop);
   var r_left = parseInt(region.offsetLeft);
   var r_right = r_left + parseInt(region.offsetWidth);
   var r_bottom = r_top + parseInt(region.offsetHeight);

    var t = Math.max(s_top, r_top);
     var r = Math.min(s_right, r_right);
     var b = Math.min(s_bottom, r_bottom);
     var l = Math.max(s_left, r_left);

      if (b > t+5  &&  r > l+5) {
          return region;
      } else {
          return null;
      }

 }

 RegionSelect.prototype.clearSelections = function(regions){
  for(var i=0; i<regions.length;i++){
   regions[i].className = regions[i].className.replaceAll(this.selectedClass,"");
  }
 }

 function getSelectedRegions(){
  return  _selectedRegions;
 }