pop：刪除原數組最后一項，并返回刪除元素的值；如果數組為空則返回undefined
var a = [1,2,3,4,5];
var b = a.pop();//a：[1,2,3,4] b：5
console.log(a, b);
push：將參數添加到原數組末尾，并返回數組的長度
var a = [1,2,3,4,5];
var b = a.push(6,7); //a：[1,2,3,4,5,6,7] b：7
concat: 返回一個新數組,是將參數添加到原數組中構成的
var a = [1,2,3,4,5];
var b = a.concat(6,7);//a：[1,2,3,4,5] b：[1,2,3,4,5,6,7]
splice(start,deleteCount,val1,val2,...)：從start位置開始刪除deleteCount項，并從該位置起插入val1,val2,...
var a = [1,2,3,4,5];
var b = a.splice(2,2,7,8,9);
console.log(a, b);
var b = a.splice(0,1); //同shift
a.splice(0,0,-2,-1);
var b = a.length; //同unshift
var b = a.splice(a.length-1,1); //同pop
console.log(b);
a.splice(a.length,0,6,7);
var b = a.length; //同push
split() 用于把一個字符串分割成字符串數組,數組一般是字符串處理比較常用的處理方法
var a = 'abcd';
var b = a.split('');
reverse: 將數組反序
var a = [1,2,3,4,5];
var b = a.reverse();//a：[5,4,3,2,1] b：[5,4,3,2,1]
sort(orderfunction)：按指定的參數對數組進行排序
var a = [1,2,3,4,5];
var b = a.sort(); //a：[1,2,3,4,5] b：[1,2,3,4,5]
join將數組的元素組起一個字符串，以separator為分隔符，省略的話則用默認用逗號為分隔符
var a = [1,2,3,4,5];
var a = [1,2,3,4,5];
var b = a.join('');//a：[1,2,3,4,5] b："12345"
