SOURCE

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

//数组从0开始
var arr = ["html","css","javascrip","wenty","gg"];
writeDoucument(arr);

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

//数组赋值
arr[4] = "bb";
writeDoucument(arr);

arr[5] = "cat";
writeDoucument(arr);

//会加空字符串
arr[8] = "dog";
writeDoucument(arr);

//获取数组长度
writeDoucument("数组的长度是"+arr.length);
//获取数组某一段
writeDoucument("数组的1-2是"+arr.slice(1,3));
//在数组头添加元素
writeDoucument(arr.unshift("web","tec"));
writeDoucument(arr);
//在数组尾添加元素
writeDoucument(arr.push("nana","nono"));
writeDoucument(arr);
//删除数组第一个元素
writeDoucument("删除元素"+arr.shift());
writeDoucument(arr);
//删除数组最后一个元素
writeDoucument("删除元素"+arr.pop());
writeDoucument(arr);

//对字符串数组按升序排序
writeDoucument(arr.sort());

var nunmArr = [3,6,9,1,4,7];
writeDoucument("排序前"+nunmArr);
//升序排列
function upcompare(a, b) {
    if(a>b){
        return 1;
    }
    if(a==b){
        return 0;
    }
    if(a<b){
        return -1;
    }
}
nunmArr.sort(upcompare);
writeDoucument("升序排序后"+nunmArr);

//定义一个降序函数
//降序排列
function downcompare(l,r) {
    if(l>r){
        return -1;
    }
    if(l==r){
        return 0;
    }
    if(l<r){
        return 1;
    }
}
nunmArr.sort(downcompare);
writeDoucument("降序排序后"+nunmArr);

//分割
writeDoucument("翻转数组"+nunmArr.reverse());
writeDoucument("默认join数组"+nunmArr.join(""));
writeDoucument("默认join数组"+nunmArr.join(":"));
writeDoucument("默认join数组"+nunmArr.join("-"));
writeDoucument("默认join数组"+nunmArr.join("><"));

var str1 = "绿叶学习网";
var str2 = str1.split("").join("><");
var arr = str2.split("");
arr.unshift("<");
arr.push(">");
var result = arr.join("");
document.write(result);

function upCompare(left, right) {
    if (left - right > 0) {
        return 1;
    }

    if (left - right == 0) {
        return 0;
    }

    if (left - right < 0) {
        return -1;
    }

}