Replacing selected with another text

Question

I am trying to replace selected text with another text.
Consider following is the line of text.

Hello world.Good morning. Hello world. Good mornin

Answer 1

You could do it like this:

SEE DEMO

function swapSelection(swapText) {
  var sel = window.getSelection ? window.getSelection() : document.selection.createRange();
  if (sel != "") {
    if (sel.getRangeAt) {
      var range = sel.getRangeAt(0);
      var newNode = document.createElement("span");
      newNode.setAttribute('class', 'swapclass');
      range.surroundContents(newNode);
    } else {
      sel.pasteHTML('' + sel.htmlText + '');

    }
    $('.swapclass').replaceWith(swapText);
  }
}

$('button').click(function () {
  swapSelection('night');
});