js数组合并

    // 第一种

    var mergeTo = [4,5,6],

          mergeFrom = [7,8,9];

    mergeTo = mergeTo.concat(mergeFrom);

    mergeTo; // is: [4, 5, 6, 7, 8, 9]

    or

    var a = [1,2], b = [3,4], c = a.concat(b);

    // 第二种

    var mergeTo = [4,5,6],

    var mergeFrom = [7,8,9];

    Array.prototype.push.apply(mergeTo, mergeFrom);

    mergeTo; // is: [4, 5, 6, 7, 8, 9]