js replace方法

str.replace(regexp|substr, newSubstr|function)

let str = "Hello, world!";
let newStr = str.replace("world", "JavaScript");
console.log(newStr); // 输出 "Hello, JavaScript!"

let str = "I have 3 apples and 5 oranges.";
let newStr = str.replace(/\d+/g, function(match) {
    return parseInt(match) * 2;
});
console.log(newStr); // 输出 "I have 6 apples and 10 oranges."

let str = "foo bar foo baz";
let newStr = str.replace(/foo/g, "qux");
console.log(newStr); // 输出 "qux bar qux baz"

let str = "I have 3 apples and 5 oranges.";
let newStr = str.replace(/\d+/g, function(match) {
    return "number: " + match;
});
console.log(newStr); // 输出 "I have number: 3 apples and number: 5 oranges."