java中的数组：
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<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<script>
//创建数组的三种方式
var arr1=[1,3,2];
var arr2=new Array(3);
var arr3=new Array(1,2,3);
document.write(arr1.length);
document.write("<hr>");
//字符串的连接操作
document.write(arr1.concat(arr3));
document.write("<hr>");
//分割字符
arr2[0]="a";
arr2[1]="b";
arr2[2]="c";
document.write(arr2);//默认是逗号
document.write("<br>");
document.write(arr2.join("**"));
document.write("<hr>");
document.write(arr2);
document.write("arr2 old length:"+arr2.length);
document.write("<hr>");
document.write(arr2.push("d"));//返回值是新数组的长度
document.write("<hr>");
document.write(arr2);
document.write("arr2 new length:"+arr2.length);
document.write("<hr>");
var arr4=["aaa","bbb","ccc","sss"];
document.write(arr4);
document.write("<hr>");
document.write("return:"+arr4.pop());
document.write("<hr>");
document.write(arr4);
document.write("<hr>");
//数组元素颠倒顺序
document.write(arr1.reverse());
</script>
<body>
</body>
</html>页面显示：
3
1,3,2,1,2,3
a,b,c
a**b**c
a,b,carr2 old length:3
4
a,b,c,darr2 new length:4
aaa,bbb,ccc,sss
return:sss
aaa,bbb,ccc
2,3,1
以下内容为转载：
2、js的Array对象
** 创建数组（三种）
- var arr1 = [1,2,3];
- var arr2 = new Array(3); //长度是3
- var arr3 = new Array(1,2,3); //数组中的元素是1 2 3
- var arr = []; //创建一个空数组
** 属性：length：查看数组的长度
** 方法
- concat方法： 数组的连接
* var arr11 = [1,2,3];
var arr12 = [4,5,6];
document.write(arr11.concat(arr12));
- join()：根据指定的字符分割数组
* var arr13 = new Array(3);
arr13[0] = "a";
arr13[1] = "b";
arr13[2] = "c";
document.write(arr13);
document.write("<br/>");
document.write(arr13.join("-"));
- push():向数组末尾添加元素，返回数组的新的长度
** 如果添加的是一个数组，这个时候把数组当做一个整体字符串添加进去
* //push方法
var arr14 = new Array(3);
arr14[0] = "tom";
arr14[1] = "lucy";
arr14[2] = "jack";
document.write("old array: "+arr14);
document.write("<br/>");
document.write("old length:"+arr14.length);
document.write("<br/>");
document.write("new length: "+arr14.push("zhangsan"));
document.write("<br/>");
document.write("new array: "+arr14);
* var arr15 = ["aaa","bbb","ccc"];
var arr16 = ["www","qqq"];
document.write("old array:"+arr15);
document.write("<br/>");
document.write("old length:"+arr15.length);
document.write("<br/>");
document.write("new length:"+arr15.push(arr16));
document.write("<br/>");
document.write("new array: "+arr15);
for(var i=0;i<arr15.length;i++) {
alert(arr15[i]);
}
- pop()：表示 删除最后一个元素，返回删除的那个元素
* var arr17 = ["zhangsan","lisi","wangwu","zhaoliu"];
document.write("old array: "+arr17);
document.write("<br/>");
document.write("return: "+arr17.pop());
document.write("<br/>");
document.write("new array: "+arr17);
- reverse():颠倒数组中的元素的顺序
* var arr17 = ["zhangsan","lisi","wangwu","zhaoliu"];
document.write("old array: "+arr17);
document.write("<br/>");
document.write("return: "+arr17.pop());
document.write("<br/>");
document.write("new array: "+arr17);
//reverse方法
document.write("<hr/>");
var arr18 = ["zhangsan1","lisi1","zhaoliu1","niuqi1"];
document.write("old array: "+arr18);
document.write("<br/>");
document.write("new array:"+arr18.reverse());
JS中的数组.
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// 定义数组. var arr1 = []; // 定义一个空数组 var arr2 = [11,22,33,44]; // 定义了一个有元素的数组. var arr3 = [11,true,'abc']; // 定义一个数组 存入不同的数据类型. 但是一般不建议这样使用.
/* for(var i = 0;i<arr3.length;i++){ alert(arr3[i]); } */ // 定义数组 使用对象定义 var arr4 = new Array(); // 定义了一个空数组. var arr5 = new Array(5); // 定义了一个长度为5的数组. //alert(arr5[0]); // alert(arr4.length); var arr6 = new Array(1,2,3,4,5,6); // 定义了一个数组 元素 1,2,3,4,5 arr6[100] = 10;
// 数组的长度是以 数组的最大下标值 + 1 alert(arr6.length);
// 面试题 /* 一下的语句那个是错误的( C ) A.var a = //; B.var a = []; C.var a = (); D.var a = {}; */ |
