CodePen

HTML

            
              <input type="checkbox" id="checkbox" value="1" checked="checked" />

<button id="checkbox_status">alert checkbox status</button>

<br />
Note how whether it is checked or not, it will always alert 'checked' when you press the button.
            
          
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CSS

            
              
            
          
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JS

            
              $(document).ready(function(){
  
  $('#checkbox_status').click(function(){
      
    alert(document.getElementById('checkbox').checked);
  
  });

});
            
          
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