JavaScript copy to clipboard not working

问题

I have a function in my script that gives me an error. The function purpose is to copy text from static panel(not textbox or input) with onClick event.

Uncaught TypeError: copyText.select is not a function

The thing i want is to make the user able to click the text and it's get copied to his clipboard.

Maybe you can offer better function that works?

https://codepen.io/abooo/pen/jYMMMN?editors=1010

function myFunction() {
  var copyText = document.getElementById("display");
  copyText.select();
  document.execCommand("Copy");
  alert("Copied the text: " + copyText.value);
}

From w3schools

回答1:

This will allow you to copy the text of an element. Though I have not tested it with complicated layout.

If you want to use this then remove the alerts and provide a better way to let the user know the content was copied.

SAFARI: This does not work on Safari before version 10.0. But as of Safari 10.0 this now works.

function copyText(element) {
  var range, selection, worked;

  if (document.body.createTextRange) {
    range = document.body.createTextRange();
    range.moveToElementText(element);
    range.select();
  } else if (window.getSelection) {
    selection = window.getSelection();        
    range = document.createRange();
    range.selectNodeContents(element);
    selection.removeAllRanges();
    selection.addRange(range);
  }
  
  try {
    document.execCommand('copy');
    alert('text copied');
  }
  catch (err) {
    alert('unable to copy text');
  }
}

<h1 id='display' onClick='copyText(this)'>Text Sample</h1>

If you want to use this on an <input> or <textarea> element then let me know the code is different.

The try/catch is for older versions of Safari that would throw an exception. So if you don't plan to support Safari before version 10.0 then you can remove it.

回答2:

Great answer by Intervalia.

Small improvement to it, sometimes the clicked element is not the one you want to copy.
So I suggest you pass the id of the element you want to copy.

<button onClick='copyText("display")'> Copy </button>
<h1 id='display'> Text Sample </h1>

And then, in the first line of your function do

element = document.getElementById(element); 

Not much of a difference but I think it's more useful this way.

回答3:

select() method is used to select the contents of text fields. it won't work on h1 element.

回答4:

hi so I looked into it and since you are not using a textInput you cannot just use the .select()function. I borrowed some code from a fellow stack overflow developer Jason on how to highlight an item in javaScript

selecting text in an element akin to highlighting with your mouse.

function selectedText(element)(){

var doc = document,
text = doc.getElementById(element)
range, selection;

if(doc.body.createTextRange){ 
 range = document.body.createTextRange();
 range.moveToElementText(text);
 range.select(); 
}
else if(window.getSelection){
  selection = window.getSelection();
  range = document.createRange();
  range.selectNodeContents(text);
  selection.removeAllRanges();
  selection.addRange(range);   
}

return range;

I then modified it to return the range. and with that all you would have to do is

document.onclick = function(e){
  if(e.target.className === 'click'){

      var copytext = SelectText('display');
      document.execCommand("copy");
      alert("Copied the text: " + copytext);
   }
}

the key part here is that the string passed in to .execCommand() is lower case 'copy'

来源：https://stackoverflow.com/questions/47931843/javascript-copy-to-clipboard-not-working