SOURCE

function writeDocument(variable){
    document.write(variable+"<br/>");
}

//数组创建
var arr = ["HTML","CSS","JavaScript","jQuery","Vue.js"];

writeDocument(arr);
//数组下标取值
writeDocument(arr[2]);

//数组赋值
arr[4]="React.js";
writeDocument(arr);

arr[5]="Vue.js";
writeDocument(arr);

arr[8]="Angular.js";
writeDocument(arr);

writeDocument("获取数组长度--------------------");
writeDocument("数组长度是："+arr.length);

writeDocument("获取数组某一段--------------------");
writeDocument("数组1-2号元素是："+arr.slice(1,3));

writeDocument("往数组头添加元素--------------------");
writeDocument(arr.unshift("Web","Technology"));
writeDocument(arr);

writeDocument("往数组尾添加元素--------------------");
writeDocument(arr.push("Bootstrap","Sass"));
writeDocument(arr);

writeDocument("删除数组的第一个元素--------------------");
writeDocument("删除元素："+arr.shift());
writeDocument(arr);

writeDocument("删除数组的最后一个元素--------------------");
writeDocument("删除元素："+arr.pop());
writeDocument(arr);

writeDocument("对字符串数组按升序排序--------------------");
writeDocument(arr.sort());

var numArr=[3,6,9,1,4,11];

writeDocument("排序前："+numArr);
function downcompare(l,r){
    if(l>r){
        return -1;
    }
    if(l==r){
        return 0;
    }
    if(l<r){
        return 1;
    }
}
numArr.sort(downcompare);
writeDocument("降序排序后："+numArr);

function upcompare(l,r){
    if(l>r){
        return 1;
    }
    if(l==r){
        return 0;
    }
    if(l<r){
        return -1;
    }
}
numArr.sort(upcompare);
writeDocument("升序排序后："+numArr);

writeDocument("反转数组："+numArr.reverse);
writeDocument("默认Join数组："+numArr.join());
writeDocument("默认Join数组："+numArr.join(":"));
writeDocument("默认Join数组："+numArr.join("-"));
writeDocument("默认Join数组："+numArr.join("><"));

function addAngleBracket(strValue){
    var strArr =strValue.split("");
    console.log(strArr);
    var str = strArr.join("><");
    console.log(str);
    strArr=str.split("");
    console.log(strArr);
    strArr.unshift("<");
    strArr.push(">");
    console.log(strArr);
    return strArr.join("");
}
writeDocument(addAngleBracket("绿叶学习网"));

function getSize(width, height, depth)
        {
            var area = width * height;
            var volume = width * height * depth;
            var sizes = [area, volume];
            return sizes;
        }
var arr = getSize(30, 40, 10);
writeDocument("底部面积为：" + arr[0] + "<br/>");
writeDocument("体积为：" + arr[1]);