全局对象，之前章节的isNaN()、isFinite()、parseInt()、parseFloat() 方法实际上都是Global 对象的方法，除此之外，还有一些其他方法。
URI编码方法
let uri = 'https://coding.imooc.com/?c=javascript';
console.log(encodeURI(uri));
//https://coding.imooc.com/?c=javascript
//本身属于uri的特殊字符不进行编码
console.log(encodeURIComponent(uri));
//https%3A%2F%2Fcoding.imooc.com%2F%3Fc%3Djavascript
//所有非标准字符进行编码
let d_uri = 'https%3A%2F%2Fcoding.imooc.com%2F%3Fc%3Djavascript';
console.log(decodeURI(d_uri));
//对应的解码
//https%3A%2F%2Fcoding.imooc.com%2F%3Fc%3Djavascript
console.log(decodeURIComponent(d_uri));
//https://coding.imooc.com/?c=javascript
eval() 方法
ES解析器
let msg = 'hello world';
eval(console.log(msg));
//hello world 等同于console.log(msg)
