Is there a closure in this immediate execution function?

question:

  • is there a closure in this code?
    • Does
  • refer to variables outside the function as closures?

Code: 

for (var i = 0; i < btns.length; iPP) {
  (function(j) {
    btns[j].onclick = function(i) {
      console.log("" + (i + 1) + "");
    };
  })(i);
}
Javascript
Nov.25,2021

to understand closures, you need to understand the JS garbage collection (GC) mechanism. this article is more specific.

as far as the landlord's question is concerned, the answer is

  • has closures, and the implied assignment is var j = I
  • function A creates a variable, function A returns a function B, and function B refers to the variable created in function A, forming a closure (GC does not automatically collect)

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