TypeError:无法读取未定义的属性(读取“”match“”)

let str = "example string";
if (str) {
  let matchResult = str.match(/example/);
  console.log(matchResult);
} else {
  console.log("字符串未定义");
}

let obj = {};
let matchResult = obj?.prop?.match(/example/);
console.log(matchResult); // 输出: undefined 而不是抛出错误

async function fetchData() {
  let response = await fetch('https://api.example.com/data');
  let data = await response.json();
  
  if (data && data.prop) {
    let matchResult = data.prop.match(/example/);
    console.log(matchResult);
  } else {
    console.log("数据未定义");
  }
}

fetchData();