var str = "";
    console.log(str.charAt(3));

    for(var i=0;i<str.length;i++){
        console.log(str.charAt(i));
    }
    console.log("=========");
    console.log(str.charCodeAt(1));
    console.log(str[1]);
    console.log("==============");
    console.log(str.concat("fujiade"));
    console.log(str.slice(0, 2));
    console.log(str.substring(0, 2));
    console.log(str.substr(2, 2));

    var str = "";
    console.log(str.indexOf('k'));
    console.log(str.lastIndexOf('o'));
    var str2 = "   sdifjos   f    "
    console.log(str2.trim());
    var str3 = "sdfjosFJDISHJOGsjdfFJOF"
    console.log(str3.toLowerCase());
    console.log(str3.toUpperCase());
    console.log("=======================");
    console.log(str.search("it"));
    console.log(str.search("i"));
    console.log(str.search("itsdf"));

    var url = "http://www./user?name=xl&pwd=lovexl&sex=女&age=2";
    function getUrlParams(url) {
        //起點(diǎn)
        var index = url.indexOf("?")+1;
        var params = url.substring(index);//沒有傳第二個(gè)值就代表著后面全都要
        var paramsArr = params.split("&");//返回一個(gè)數(shù)組
        console.log(paramsArr);
        var obj = {};
        paramsArr.forEach(function (value, index, array) {
            console.log(value);
            var tempArr = value.split("=");
            obj[tempArr[0]] = tempArr[1];
            console.log(obj);
        });
        return obj;
    }
    var obj = getUrlParams(url);
    console.log(obj);