js if 对象

let myObject;

if (myObject) {
  console.log('对象存在');
} else {
  console.log('对象不存在或为null');
}

let person = { name: 'Alice', age: 25 };

if ('name' in person) {
  console.log('person对象有name属性');
} else {
  console.log('person对象没有name属性');
}

if (person.hasOwnProperty('name')) {
  console.log('person对象有name属性');
}

if (person.age > 18) {
  console.log('Alice已成年');
} else {
  console.log('Alice未成年');
}

if (Object.keys(myObject).length === 0) {
  console.log('对象为空');
} else {
  console.log('对象不为空');
}

if (typeof myObject.myMethod === 'function') {
  console.log('myObject有myMethod方法');
} else {
  console.log('myObject没有myMethod方法');
}