编辑代码

const str = 'Hello ,World';

const price = 12.545;

str2 = Array.from(str);

console.log(str.length);

console.log(price.toFixed(0));



console.log(str.split(','));
console.log(str.substring(str.length,1));
console.log(str.startsWith('e',1));
console.log(str.includes('d',str.length-1));

console.log(str.toUpperCase());
console.log(str.toLowerCase());


console.log(str.indexOf(',World'));
console.log(str.endsWith('d'));

str3 = str.replace(/rld/,'RLD');

console.log(str3);

console.log(str3.match(/RLD/));