Changing the context of a function in JavaScript -


This is taken from the advanced JavaScript # 25 of John Recife, which is called changing the context of the function.

1) In line fn () == what is it mentioned? Does it mention it inside the ceremony where it says that it comes back?

2) Although I understand the purpose of the last line (to attach a specific object to the function), I do not know how it codifies. Is the word "call" a pre-defined javascript function? In plain language, please explain "fn.call (object)", and clearly tell me if P>

3). After the function is assigned to the object, do you have object.fn (); ? 

  var object = {} will call that function? Function (fn) () this return; } Insert (fn () == This, "Reference is a global object."); (Object) == object, "Context has been changed to a specific object."  
 
 is a function defined for a  function  object. The first parameter for  call  is the object which is the reference to  this  function is being called.  
 When  fn ()  is called without any special reference,  refers to this  global context, or  window  Browser environment This rule is applied in the global criteria of  this , hence  fn () == this) ,  this  refers to the global object However, when it is said in the context of another object, as in  fn.call (object) , then  it  inside  fn  Refers to  Object .  
  does not modify or assign anything to fn.call (object)  to  object . The only affected code is  this  inside the value of  fn  for the duration of that call. Even after this call, you will continue to  fn () , and  object.fn () . Not in the form of   
 The example only indicates that the  this  value is dynamic inside the function.   

 


  








































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