SOURCE

function writeDocument(variable) {
    document.write(variable + "<br/>");
} 
var arr=['HTML','css','javascript','vable','giao'];
writeDocument(arr);
writeDocument(arr.length);
writeDocument(arr.slice(1, 3));
arr.push('yellow','dog','pig');
writeDocument(arr);
arr.unshift('miao','loser');
writeDocument(arr);

writeDocument("对字符串数组进行升序的排序------");
writeDocument(arr.sort());

var numArr=[3,4,11,12,9,10];

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

writeDocument("打印排序前的数字数组"+'<br/>'+numArr);
writeDocument("打印升序后的数字数组"+'<br/>'+numArr.sort(upCompare));
writeDocument("打印降序后的数字数组"+'<br/>'+numArr.sort(dowmCompare));
writeDocument("反转数组------------------------");
writeDocument(numArr.reverse());
writeDocument(numArr.join(":"));

writeDocument("数字符添加括号-----------");
writeDocument("给字符添加尖括号--------------");
function addAngleBracket(strValue){
    var strArr=strValue.split("");
    var strArr1=strArr.join("><");
    strArr=strArr1.split("");
    strArr.unshift("<");
    strArr.push(">");
    return strArr.join("");
}
var strValue = "绿叶学习网";
writeDocument(strValue);
writeDocument(addAngleBracket(strValue));