Why is this variable used in the function?

• 0
  DD, help me plz !, though I don't understand why var self = this is used, as well as this is generally assigned, I read that it is used to use the main context of the function in nested functions, but for some reason in a simple example
  

  function a() {
      let self = this; // widnow
      console.log(this); 
      var fn = function () {
        console.log(this); //widnow
        console.log(self); // function a
      };
      fn();
    }
    a();

  
  but it turns out that all console.log references the window object

  JavaScript Kira Bentley, Feb 16, 2020

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2 Answers
• 0
  I advise you to read for understanding:
  
  Object methods, "this" (RU)

  Arabella Beard

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• 0
  Wrong example (
  
  
  
  

  function a() {
  
      let self = this; // widnow
  
      console.log(this); 
  
      var fn = function () {
  
        console.log(this); //widnow
  
        console.log(self); // function a - widnow
  
      };
  
      fn();
  
    }
  
    a();

  Anonymous

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