Make a instead of by pressing Enter on a contenteditable

In order to solve your problem, always keep a br element as the last element of your contenteditable div. This will ensure predictable behavior when injecting a br element vs. the browser default of injecting div elements. You can check the lastChild on keyup and mouseup to make sure it’s a br element. Assuming you have a document like:

<div id="editable" contenteditable="true"></div>

You can use the following JavaScript (w/ jQuery 1.4+) to keep a br element as the last element and inject a br element instead of div div:

$(function(){

  $("#editable")

    // make sure br is always the lastChild of contenteditable
    .live("keyup mouseup", function(){
      if (!this.lastChild || this.lastChild.nodeName.toLowerCase() != "br") {
        this.appendChild(document.createChild("br"));
      }
    })

    // use br instead of div div
    .live("keypress", function(e){
      if (e.which == 13) {
        if (window.getSelection) {
          var selection = window.getSelection(),
              range = selection.getRangeAt(0),
              br = document.createElement("br");
          range.deleteContents();
          range.insertNode(br);
          range.setStartAfter(br);
          range.setEndAfter(br);
          range.collapse(false);
          selection.removeAllRanges();
          selection.addRange(range);
          return false;
        }
      }
    });

});

Tested on Apple OS X w/ Google Chrome 7, Mozilla Firefox 3.6, Apple Safari 5). Try using ierange to get this to work in Windows Internet Explorer.