JS到达并使用父对象的变量

var obj = {
  parentVariable: "Hello",
  childMethod: function() {
    console.log(this.parentVariable);
  }
};

obj.childMethod(); // 输出：Hello

var obj = {
  parentVariable: "Hello",
  childMethod: function() {
    var self = this;
    return function() {
      console.log(self.parentVariable);
    };
  }
};

var child = obj.childMethod();
child(); // 输出：Hello

function Parent() {
  this.parentVariable = "Hello";
}

Parent.prototype.getParentVariable = function() {
  return this.parentVariable;
};

function Child() {
  // 子对象继承父对象
}

Child.prototype = Object.create(Parent.prototype);
Child.prototype.constructor = Child;

var child = new Child();
console.log(child.getParentVariable()); // 输出：Hello