javascript - Add eventlistener to canvas tag -

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I get the canvas tag correctly from HTML, but when I make it an event Try, console returns me unchecked typed error: there is no undefined function . I do not understand the reason. 

  var x = document.getElementsByTagName ('canvas'); Console.log (x); // Print correctly elements: [canvas, item: function, named: function] x.addEventListener ("click", provision); // UnkitType Error: Undefined No Function Function (Event) {console.log ("Prova"); //};    
 
 
  document.getElementsByTagName ("canvas") [0]   
  getElementsByTagName  returns an HTMLCollection (like an array), and works on the  addEventListener  elements, so that you You need to select the correct index.  
 An optional  document.query selector ("canvas") is  which will return an element.

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