Inserting a text where cursor is using Javascript/jquery

Question

I have a page with a lot of textboxes. When someone clicks a link, i want a word or two to be inserted where the cursor is, or appended to the textbox which has the focus.<

Answer 1

The code above didn't work for me in IE. Here's some code based on this answer.

I took out the getElementById so I could reference the element in a different way.

function insertAtCaret(element, text) {
  if (document.selection) {
    element.focus();
    var sel = document.selection.createRange();
    sel.text = text;
    element.focus();
  } else if (element.selectionStart || element.selectionStart === 0) {
    var startPos = element.selectionStart;
    var endPos = element.selectionEnd;
    var scrollTop = element.scrollTop;
    element.value = element.value.substring(0, startPos) +
      text + element.value.substring(endPos, element.value.length);
    element.focus();
    element.selectionStart = startPos + text.length;
    element.selectionEnd = startPos + text.length;
    element.scrollTop = scrollTop;
  } else {
    element.value += text;
    element.focus();
  }
}

input{width:100px}
label{display:block;margin:10px 0}

Copy text from: 
Element to insert: 
Insert

EDIT: Added a running snippet, jQuery is not being used.