javascript数组的几种写法

ArrI=new Array();
ArrI[0] = new Array("username1","0","609");
ArrI[1] = new Array("username2","609","610");
ArrI[2] = new Array("username3","609","611");

ArrII=new Array(
new Array("username1","0","609"),
new Array("username2","609","610"),
new Array("username3","609","611")
);

ArrIII=[];
ArrIII[0] = new Array("username1","0","609");
ArrIII[1] = new Array("username2","609","610");
ArrIII[2] = new Array("username3","609","611");

ArrIIII=[
["username1","0","609"],
["username2","609","610"],
["username3","609","611"]
];

感觉最后一种写法比较好，占用空间最小。