比较新旧两个数组值得增加和删除的JS代码_javascript技巧

　　以前项目中用到自己写的，应该没有bug吧，有更好的也欢迎大家指教，
var Return_AddStrFn=function (oldArr, newArr) {
        var t = this;
　　　　　　　//去重复的方法
        Array.prototype.unique4 = function () {
            // this = arr;
            var temp = new Array();
            this.sort();
            for (i = 0; i                 if (this[i] == this[i + 1]) {
                    continue;
                }
                temp[temp.length] = this[i];
            }
            return temp;
        }
        var a = d = oldArr.unique4(); //旧数组
        var b = e = newArr.unique4();//新数组
        var c = [];
        var dels = [];
        function f() {
            a.sort();
            b.sort();
            var i = 0;
            var j = 0;
            while (i                 if (a[i]                     c.push(a[i]);
                    i++;
                } else if (b[j]                     c.push(b[j]);
                    j++;
                } else {
                    i++;
                    j++;
                }
            }
            while (i                 c.push(a[i]);
                i++;
            }
            while (j                 c.push(b[j]);
                j++;
            }
        }
        f();
        //alert("c:" + c);
        //alert("d:" + d);
        var addstr = [];
        for (var i = 0; i             for (var j = 0; j                 if (e[j] == c[i]) {
                    addstr.push(e[j]);
                }
            }
        }
        return addstr; //新增的
        //for (var i = 0; i         //    for (var j = 0; j         //        if (d[j] == c[i]) {
        //            dels.push(d[j]);
        //        }
        //    }
        //}
        //alert("dels:" + dels); //删除的
    }