concat() slice()

concat()

连接2个或者多个数组

var v1 = ["1","2","3"],v2 = ["4","5","6",9,8],v3;

v3 = v1.concat(v2,["m",99,8]);     

slice();

var color=["red","blue","green","yellow","orange"];

var newColors=color.slice(1,2);

var newColors=color.slice(-2,4);　　 //输出结果为yellow;   负数的时候总长度减去该负数    （3，4）

document.write(newColors);   //输出结果为green;