Javascript 原始方法

var name = "Javascript is easy"; 
var lowercaseName = name.toLowerCase();     
var firstLetter = name.charAt(0);           
var middleOfName = name.substring(4, 10);   

console.log(lowercaseName);
console.log(firstLetter);
console.log(middleOfName);

var count = 10; 
var fixedCount = count.toFixed(2);          
var hexCount = count.toString(16);   

console.log(fixedCount);
console.log(hexCount);

var flag = true; 
var stringFlag = flag.toString();           

console.log(stringFlag);