手写 call 和 apply

Function.prototype.call2 = function(ctx, ...params) {
  if (typeof ctx == 'object') {
    ctx = ctx || window;
  } else {
    ctx = Object(ctx);
  }
  ctx.fn = this;
  var result = ctx.fn(...params);
  delete ctx.fn;
  return result;
};
var name = 'windowName';
var obj = {
  name: 'obgMarin',
};

function getName(age, name) {
  console.log(this.name);
  console.log(age, name);
}
getName.call2(obj, 12, '123');
getName.call2(null, 12, '123');