如何测试对象属性的名称？

Question

我有一个对象，我想测试属性的名称，而不是内容而是名称。我无法实现它：

theCtns = {
  "services": {
    "a": {
      "image": "a"
    },
    "b": {
      "image": "b"
    }
  }

alreadyExistSrv = false;
regex = new RegExp('(^|\\s)' + "b" + '(?=\\s|$)', 'g');
for (var service in theCtns.services) {
  if (regex.test(theCtns.services[service])){
    alreadyExistSrv = true;
  }
}

if(alreadyExistSrv){
  console.log("the name is free");
}else{
  console.log("the name already exists");
}

alreadyExistSrv = false;
regex = new RegExp('(^|\\s)' + "bb" + '(?=\\s|$)', 'g');
for (var service in theCtns.services) {
  if (regex.test(theCtns.services[service])){
    alreadyExistSrv = true;
  }
}

if(alreadyExistSrv){
  console.log("the name is free");
}else{
  console.log("the name already exists");
}

因此，当我在正则表达式中使用"b"时，它应该说the name already exists，当我使用"bb"时，它应该说the name is free