document.getElementById("copyButton").addEventListener("click",function(){
copyToClipboard(document.getElementById("copyTarget"));});function copyToClipboard(elem){// create hidden text element, if it doesn't already existvar targetId ="_hiddenCopyText_";var isInput = elem.tagName ==="INPUT"|| elem.tagName ==="TEXTAREA";var origSelectionStart, origSelectionEnd;if(isInput){// can just use the original source element for the selection and copy
target = elem;
origSelectionStart = elem.selectionStart;
origSelectionEnd = elem.selectionEnd;}else{// must use a temporary form element for the selection and copy
target = document.getElementById(targetId);if(!target){var target = document.createElement("textarea");
target.style.position ="absolute";
target.style.left ="-9999px";
target.style.top ="0";
target.id = targetId;
document.body.appendChild(target);}
target.textContent = elem.textContent;}// select the contentvar currentFocus = document.activeElement;
target.focus();
target.setSelectionRange(0, target.value.length);// copy the selectionvar succeed;try{
succeed = document.execCommand("copy");}catch(e){
succeed =false;}// restore original focusif(currentFocus &&typeof currentFocus.focus ==="function"){
currentFocus.focus();}if(isInput){// restore prior selection
elem.setSelectionRange(origSelectionStart, origSelectionEnd);}else{// clear temporary content
target.textContent ="";}return succeed;}