js 数组去除重复项

转自司超云，连接地址忘记了。。

//去除已选检查项数组中重复项

 var compare = compare || {};

    compare.array = compare.array || {};

 compare.array.unique = function (source, compareFn) {

     var len = source.length,

         result = source.slice(0),

         i, datum;

        

     if ('function' != typeof compareFn) {

         compareFn = function (item1, item2) {

             return item1 === item2;

         };

     }

     // 从后往前双重循环比较

     // 如果两个元素相同，删除后一个

     while (--len > 0) {

         datum = result[len];

         i = len;

         while (i--) {

             if (compareFn(datum, result[i])) {

                 result.splice(len, 1);

                 break;

             }

         }

     }

     return result;

 };