JavaScript中的Array 对象（数组对象）

arr[0] == 1;
arr[1] == 2;
arr[2] == 3;
--->new Array();
var arr = new Array();//定义一个没有任何内容的数组对象，然后以下面的方式为其赋值
arr[0] = "arr0";
arr[1] = "arr1";
arr[2] = "arr2";
--->new Array(size);//定义一个大小有限制的数组对象，然后以下面的方式赋值（赋值方式和上面是一样的）
var arr = new Array(3);
arr[0] = "arr0";
arr[1] = "arr1";
arr[2] = "arr2";
--->new Array(element0, element1, ..., elementn);//直接将数组内容定义好
var arr = new Array("arr0","arr1","arr2");

arr[0] == "arr0";
arr[1] == "arr1";
arr[2] == "arr2";

var arr = new Array(3);
if(arr.constructor==Array)
{
document.write("This is an Array");
}
if (test.constructor==Boolean)
{
document.write("This is a Boolean");
}
if (test.constructor==Date)
{
document.write("This is a Date");
}
if (test.constructor==String)
{
document.write("This is a String");
}

--->length，即Array的长度
var arr = new Array(3);
document.write(arr.length);//输出结果是3

arr.length=5;
document.write(arr.length);//输出结果是5
--->prototype,使您有能力向对象添加属性和方法。
function myarray(name,age)//定义一个类，此类目前有两个属性
{
this.name = name;
this.age = age;
}
var myarr = new myarray("john",25);
myarray.prototype.test = null;//为myarray类添加了一个属性
myarr.test = "test";
alert(myarr.test);//输出test

var arr = new Array(1,2,3);
alert(arr.concat(4,5));//输出1,2,3,4,5

var arr1 = new Array(1,2,3);
var arr2 = [4,5];
var arr3 = new Array("jone","john");
alert(arr1.concat(arr2,arr3));//输出1,2,3,4,5,jone,john

--->无参
var arr = new Array("jone","Grrgy","john");
alert(arr.join());//输出jone,Grrgy,john 字符串中间以,隔开
--->有参
var arr = new Array("jone","Grrgy","john");
alert(arr.join("."));//输出jone.Grrgy.john 字符串中间以参数隔开

var arr = new Array("jone","john","grrgy");
document.write(arr.pop());//输出内容：grrgy
document.write(arr.join("-"));//输出：jone-john

var arr = ["jone","john","grrgy"];
document.write(arr.push("tom"));//输出：4（长度）
document.write(arr.join());//输出：jone,john,grrgy,tom

var arr = ["jone","john","grrgy"];
document.write(arr.reverse());//grrgy,john,jone

var arr = ["jone","john","grrgy"];
document.write(arr.shift());//输出：jone
document.write(arr.join());//输出：jone,john

var arr = ["jone","john","grrgy","tom","hell"];
var test = arr.slice(1);
if(test.constructor==Array)
{
document.write("This is an Array<br>");
document.write(test.join());
}

var test = arr.slice(1,2);

var arr = ["jone","john","grrgy","tom","hell"];
document.write(arr.sort());
document.write("<br>");
document.write(arr);

function sortNumber(a,b)// 定义排序规则的函数
{
if(a>b)
{
return 1;
}
else if(a<b)
{
return -1;
}
else
{
return 0;
}

}
var arr = new Array(1,2000,3,400);
document.write(arr.sort(sortNumber));//此处只写函数名即可
document.write("<br>");
document.write(arr);

--->只插入
var arr = new Array(6);
arr[0] = "George";
arr[1] = "John";
arr[2] = "Thomas";
arr[3] = "James";
arr[4] = "Adrew";
arr[5] = "Martin";
document.write(arr + "<br />");
arr.splice(2,0,"William");
document.write(arr + "<br />");

--->只删除
var arr = new Array(6);
arr[0] = "George";
arr[1] = "John";
arr[2] = "Thomas";
arr[3] = "James";
arr[4] = "Adrew";
arr[5] = "Martin";
document.write(arr + "<br />");
arr.splice(2,1);
document.write(arr + "<br />");

--->既删除又添加（相当于替换）
var arr = new Array(6);
arr[0] = "George";
arr[1] = "John";
arr[2] = "Thomas";
arr[3] = "James";
arr[4] = "Adrew";
arr[5] = "Martin";
document.write(arr + "<br />");
arr.splice(2,1,"William");
document.write(arr + "<br />");

var myarr = new Array('lisi',25);
document.write(myarr.toSource());

function myarray(name,age)
{
this.name = name;
this.age = age;
}
var myarr = new myarray('lisi',25);
document.write(myarr.toSource());

var myarr = new Array('jone','john','Tom');
document.write(myarr.join('.'));
document.write('<br>');
document.write(myarr.join(','));
document.write('<br>');
document.write(myarr.join());
document.write('<br>');
document.write(myarr.toString());

var myarr = new Array('jone','john','Tom');
var length = myarr.unshift('zhangsan','lisi');
document.write(myarr);
document.write('<br>');
document.write(length);