JavaScript数组去重（数组去掉重复元素）

<script>/** * 利用JavaScript内置的hash去重数组中的重复元素 * @author kanpiaoxue * date 2011/08/29 13:29:01 */function uniqueArray(arr){if(null == arr || arr.length == 0 ){return arr;}else{var innerHashMap = {};for(var i = 0, j = arr.length; i<j; i++){innerHashMap[arr[i]] = null;}var rs = [];for (obj in innerHashMap){rs.push(obj);}return rs;}}/*------------------------ test ---------------------------*/var arr = [1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0];var arr1 = [];for(var i = 0 ; i < 10; i++){arr1[i] = 'element' + (i%2);}//alert('source: ' + arr + '\n' + 'target: ' + uniqueArray(arr) + '\n' + 'source: ' +  arr1 + '\n' + 'target: ' +  uniqueArray(arr1))var longArr = []for(var i = 0; i < 100000; i++){longArr[i] = i;}var start = (new Date()).getTime();uniqueArray(longArr);var end = (new Date()).getTime();alert((end - start) + 'ms');</script>