How to disable or enable copy paste cut disable in Textbox

Change the properties - For disable

 Oncopy="return false"

 Onpaste="return false"

 Oncut="return false"

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Change the properties - For enable

 Oncopy="return true"

 Onpaste="return true"

 Oncut="return true"

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For enable copy, cut, paste in javascript

document.getElementById('form1').onpaste = 'return true';

document.getElementById('form1').oncopy = 'return true';

document.getElementById('form1').oncut = 'return true';

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For enable copy paste by javascript function

function test(){

var elems = document.getElementById('form1');

   var attrs = ['onpaste','oncopy','oncut'];

   for (i = 0; i < elems.length; i++) {

      for (j = 0; j < attrs.length; j++) {

         if (elems[i].getAttribute(attrs[j])) {

            elems[i].setAttribute(attrs[j],elems[i]

            .getAttribute(attrs[j])

            .replace("return false","return true"));

         }

      }

   }

}