String(JavaScript) 对象方法

var txt = new String("string");
// 或者更简单方式
var txt = "string";

var txt = "Hello World!";
txt.constructor//function String() { [native code] }

var txt = "Hello World!";
txt.length//12

function employee(name,jobtitle,born){
    this.name=name;
    this.jobtitle=jobtitle;
    this.born=born;
}
var fred=new employee("Fred Flintstone","Caveman",1970);
employee.prototype.salary=null;
fred.salary=20000;

var str = "HELLO WORLD";
str.charAt(2)// L

var str = "HELLO WORLD";
str.charCodeAt(0)// 72

var str1 = "Hello ";
var str2 = "world!";
var n = str1.concat(str2);// Hello world!

let str = "Hello world";
str.endsWith("world")   // 返回 true
str.endsWith("World")   // 返回 false

var n = String.fromCharCode(65);// A

var str="Hello world, welcome to the universe.";
var n=str.indexOf("welcome");// 13

var str = "Hello world, welcome to the Runoob。";
var n = str.includes("world");// true

var str="I am from runoob，welcome to runoob site.";
var n=str.lastIndexOf("runoob");// 28

var str="The rain in SPAIN stays mainly in the plain"; 
var n=str.match(/ain/g);// ain,ain,ain

var str = "a";
str.repeat(2);// aa

var str="Visit Microsoft! Visit Microsoft!";
var n=str.replace("Microsoft","a");
//Visit a!Visit Microsoft!

var str="Visit Microsoft! Visit Microsoft!";
var n=str.replaceAll("Microsoft","a");
//Visit a!Visit a!

var str="Visit a!"; 
var n=str.search("a");//6

var str="Hello world!";
var n=str.slice(1,5);// ello

var str="How are you doing today?";
var n=str.split(" ");
//How,are,you,doing,today?

var str = "Hello world, welcome to the Runoob.";
var n = str.startsWith("Hello");// true

var str="Hello world!";
var n=str.substr(2,3)// llo

var str="Hello world!";
str.substring(3);// lo world!
str.substring(3,7);// lo w

var str="world!";
str.toLowerCase();//world!

var str="world!";
str.toUpperCase();//WORD!

var str = "       a        ";
alert(str.trim());//a

var str = "Aa";
var res = str.toLocaleLowerCase();// aa

var str = "Aa";
var res = str.toLocaleUpperCase();// AA

var str="Hello world!";
str.valueOf();// Hello world!

var str = "a";
var res = str.toString();// a

var txt="Chapter 10";
txt.anchor("chap10");
alert(txt.anchor("chap10"));

var txt = "Hello World!";
document.write("<p>字体变大: " + txt.big() + "</p>");
document.write("<p>字体缩小: " + txt.small() + "</p>");
document.write("<p>字体加粗: " + txt.bold() + "</p>");
document.write("<p>斜体: " + txt.italics() + "</p>");
document.write("<p>固定定位: " + txt.fixed() + "</p>");
document.write("<p>加删除线: " + txt.strike() + "</p>");
document.write("<p>字体颜色: " + txt.fontcolor("green") + "</p>");
document.write("<p>字体大小: " + txt.fontsize(6) + "</p>");
document.write("<p>下标: " + txt.sub() + "</p>");
document.write("<p>上标: " + txt.sup() + "</p>");
document.write("<p>链接: " + txt.link("http://www.w3cschool.cc") + "</p>");
document.write("<p>闪动文本: " + txt.blink() + " (不能用于IE,Chrome,或者Safari)</p>")