本篇文章主要是对JavaScript简单实现鼠标拖动选择功能的示例代码进行了介绍，需要的朋友可以过来参考下，希望对大家有所帮助
代码如下:
<style><!--
body{padding-top:50px;padding-left:100px;padding-right:150px;}
.fileDiv{float:left;width:100px;height:100px;text-align:center;line-height:100px;font-size:12px;border:1px solid #cccccc;margin-right:10px;margin-bottom:10px;}
.seled{border:1px solid #ff0000;background-color:#D6DFF7;}
--></style>
<script type="text/javascript">// <![CDATA[
Array.prototype.remove = function( item ){
for( var i = 0 ; i < this.length ; i++ ){
if( item == this[i] )
break;
}
if( i == this.length )
return;
for( var j = i ; j < this.length - 1 ; j++ ){
this[ j ] = this[ j + 1 ];
}
this.length--;
}
String.prototype.replaceAll = function (AFindText,ARepText){ raRegExp = new RegExp(AFindText,"g"); return this.replace(raRegExp,ARepText);}
function getAllChildren(e) {
return e.all ? e.all : e.getElementsByTagName('*');
}
document.getElementsBySelector = function(selector) {
if (!document.getElementsByTagName) {
return new Array();
}
var tokens = selector.split(' ');
var currentContext = new Array(document);
for (var i = 0; i < tokens.length; i++) {
token = tokens[i].replace(/^s+/,'').replace(/s+$/,'');;
if (token.indexOf('#') > -1) {
var bits = token.split('#');
var tagName = bits[0];
var id = bits[1];
var element = document.getElementById(id);
if (tagName&&element.nodeName.toLowerCase() != tagName) {
return new Array();
}
currentContext = new Array(element);
continue;
}
if (token.indexOf('.') > -1) {
var bits = token.split('.');
var tagName = bits[0];
var className = bits[1];
if (!tagName) {
tagName = '*';
}
var found = new Array;
var foundCount = 0;
for (var h = 0; h < currentContext.length; h++) {
var elements;
if (tagName == '*') {
elements = getAllChildren(currentContext[h]);
} else {
elements = currentContext[h].getElementsByTagName(tagName);
}
for (var j = 0; j < elements.length; j++) {
found[foundCount++] = elements[j];
}
}
currentContext = new Array;
var currentContextIndex = 0;
for (var k = 0; k < found.length; k++) {
if (found[k].className&&found[k].className.match(new RegExp('\b'+className+'\b'))) {
currentContext[currentContextIndex++] = found[k];
}
}
continue;
}
if (token.match(/^(w*)[(w+)([=~|^$*]?)=?"?([^]"]*)"?]$/)) {
var tagName = RegExp.$1;
var attrName = RegExp.$2;
var attrOperator = RegExp.$3;
var attrValue = RegExp.$4;
if (!tagName) {
tagName = '*';
}
var found = new Array;
var foundCount = 0;
for (var h = 0; h < currentContext.length; h++) {
var elements;
if (tagName == '*') {
elements = getAllChildren(currentContext[h]);
} else {
elements = currentContext[h].getElementsByTagName(tagName);
}
for (var j = 0; j < elements.length; j++) {
found[foundCount++] = elements[j];
}
}
currentContext = new Array;
var currentContextIndex = 0;
var checkFunction;
switch (attrOperator) {
case '=':
checkFunction = function(e) { return (e.getAttribute(attrName) == attrValue); };
break;
case '~':
checkFunction = function(e) { return (e.getAttribute(attrName).match(new RegExp('\b'+attrValue+'\b'))); };
break;
case '|':
checkFunction = function(e) { return (e.getAttribute(attrName).match(new RegExp('^'+attrValue+'-?'))); };
break;
case '^':
checkFunction = function(e) { return (e.getAttribute(attrName).indexOf(attrValue) == 0); };
break;
case '$':
checkFunction = function(e) { return (e.getAttribute(attrName).lastIndexOf(attrValue) == e.getAttribute(attrName).length - attrValue.length); };
break;
case '*':
checkFunction = function(e) { return (e.getAttribute(attrName).indexOf(attrValue) > -1); };
break;
default :
checkFunction = function(e) { return e.getAttribute(attrName); };
}
currentContext = new Array;
var currentContextIndex = 0;
for (var k = 0; k < found.length; k++) {
if (checkFunction(found[k])) {
currentContext[currentContextIndex++] = found[k];
}
}
continue;
}
tagName = token;
var found = new Array;
var foundCount = 0;
for (var h = 0; h < currentContext.length; h++) {
var elements = currentContext[h].getElementsByTagName(tagName);
for (var j = 0; j < elements.length; j++) {
found[foundCount++] = elements[j];
}
}
currentContext = found;
}
return currentContext;
}
function addEvent(eventType,eventFunc,eventObj){
eventObj = eventObj || document;
if(window.attachEvent)eventObj.attachEvent("on"+eventType,eventFunc);
if(window.addEventListener) eventObj.addEventListener(eventType,eventFunc,false);
}
function clearEventBubble(evt){
evt = evt || window.event;
if (evt.stopPropagation) evt.stopPropagation(); else evt.cancelBubble = true;
if (evt.preventDefault)evt.preventDefault();else evt.returnValue = false;
}
function posXY(event){
event = event || window.event;
var posX = event.pageX || (event.clientX +
(document.documentElement.scrollLeft || document.body.scrollLeft));
var posY = event.pageY || (event.clientY +
(document.documentElement.scrollTop || document.body.scrollTop));
return {x:posX, y:posY};
}
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;
}
function showSelDiv(){
var selInfo = "";
var arr = getSelectedRegions();
for(var i=0; i<arr.length;i++){
selInfo += arr[i].innerHTML+"n";
}
alert("共选择 "+arr.length+" 个文件，分别是：n"+selInfo);
}
// ]]></script>
<p><button onclick="showSelDiv();">getRegions</button></p>
<div class="fileDiv">file1</div>
<div class="fileDiv">file2</div>
<div class="fileDiv">file3</div>
<div class="fileDiv">file4</div>
<div class="fileDiv">file5</div>
<div class="fileDiv">file6</div>
<div class="fileDiv">file7</div>
<div class="fileDiv">file8</div>
<div style="float: left; width: 100%;"><button onclick="showSelDiv();">getRegions</button></div>
<script type="text/javascript">// <![CDATA[
new RegionSelect({
region:'div.fileDiv',
selectedClass: 'seled'
}).select();
// ]]></script>
