如何在JavaScript正则表达式中访问匹配的组？

const regex = /(\w+)\s(\w+)/;
const str = "John Doe";
const matches = str.match(regex);

if (matches) {
  console.log(matches[0]); // 输出完整匹配结果："John Doe"
  console.log(matches[1]); // 输出第一个捕获组："John"
  console.log(matches[2]); // 输出第二个捕获组："Doe"
}

const regex = /(\w+)\s(\w+)/;
const str = "John Doe";
const matches = regex.exec(str);

if (matches) {
  console.log(matches[0]); // 输出完整匹配结果："John Doe"
  console.log(matches[1]); // 输出第一个捕获组："John"
  console.log(matches[2]); // 输出第二个捕获组："Doe"
}

const regex = /(\w+)\s(\w+)/;
const str = "John Doe";
const newStr = str.replace(regex, (match, p1, p2) => {
  console.log(match); // 输出完整匹配结果："John Doe"
  console.log(p1); // 输出第一个捕获组："John"
  console.log(p2); // 输出第二个捕获组："Doe"
  return match;
});