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const person = {
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};
person.getName(); // Êä³ö: John

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function getName() {
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getName(); // Êä³ö: undefined (Ö¸ÏòÈ«¾Ö¹¤¾ß)

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function Person(name) {
  this.name = name;
}
const person1 = new Person("John");
console.log(person1.name); // Êä³ö: John

// ͨ¹ý call() ŲÓÃ
const obj = {
  name: "Jane"
};
getName.call(obj); // Êä³ö: Jane

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