How to create a bulkhead by class?

• 0

  <span class="allow"> 1 </span>
  <span class="allow"> 2 </span>
  <span class="allow"> 3 </span>
  <span class="allow"> 4 </span>
  <span class="deny"> 5 </span>

  
  

  var d = document.getElementsByClassName("allow");
  d.forEach((e) => {
  e.style = "backgound: red;"
  })

  
  
  How can I change a property of elements through a class? And then I have an error that there is no function even though foreach, as if a function, I do not understand how to solve this.
  Please show on js.

  JavaScript Adam Drake, Jun 22, 2020

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2 Answers
• 0
  You have an HTMLCollection, not an array, so there is no forEach.
  
  
  
  Two options:
  
  1. [... document.getElementsByClassName ("allow")] to transfer to an array, and then do forEach
  
  2. If you don't need a Live collection of elements, use querySelectorAll to find the elements.
  
  
  
  Option # 2 is usually preferred.
  
  
  
  And, don't change the entire style property, just the desired style:
  
  e.style.background = 'red';
  
  
  
  Therefore, if you write everything as short as possible, then:
  
  

  [...document.querySelectorAll('.allow')].forEach(element => {
  
    element.style.background = 'red';
  
  });

  Vivienne Coleman

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• 0
  Everything is described in detail here

  Anonymous

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