转载地址：http://dmitrysoshnikov.com/ecmascript/chapter-3-this/
Introduction
In this article we will discuss one more detail directly related with execution contexts. The topic of discussion is the this keyword.
As the practice shows, this topic is difficult enough and often causes issues in determination ofthis value in different execution contexts.
Many programmers are used to thinking that the this keyword in programming languages is closely related to the object-oriented programming, exactly referring the newly created object by the constructor. In ECMAScript this concept is also implemented, however, as we will see, here it is not limited only to definition of created object.
Let’s see in detail what exactly this value is in ECMAScript.
Definitions
this value is a property of the execution context:
activeExecutionContext = { VO: {...},
this: thisValue
};