Here's an example using simple DOM methods, based on other answers I've provided on Stack Overflow. It also uses Rangy to save and restore the selection while doing the substitutions so that the caret does not move.
Demo:
http://jsbin.com/zuvevocu/2
Code:
var editorEl = document.getElementById("editor");
var keyTimer = null, keyDelay = 100;
function createKeyword(matchedTextNode) {
var el = document.createElement("b");
el.style.backgroundColor = "yellow";
el.style.padding = "2px";
el.contentEditable = false;
var matchedKeyword = matchedTextNode.data.slice(1, -1); // Remove the curly brackets
matchedTextNode.data = (matchedKeyword.toLowerCase() == "name") ? "John Smith" : "REPLACEMENT FOR " + matchedKeyword;
el.appendChild(matchedTextNode);
return el;
}
function surroundInElement(el, regex, surrounderCreateFunc) {
// script and style elements are left alone
if (!/^(script|style)$/.test(el.tagName)) {
var child = el.lastChild;
while (child) {
if (child.nodeType == 1) {
surroundInElement(child, regex, surrounderCreateFunc);
} else if (child.nodeType == 3) {
surroundMatchingText(child, regex, surrounderCreateFunc);
}
child = child.previousSibling;
}
}
}
function surroundMatchingText(textNode, regex, surrounderCreateFunc) {
var parent = textNode.parentNode;
var result, surroundingNode, matchedTextNode, matchLength, matchedText;
while ( textNode && (result = regex.exec(textNode.data)) ) {
matchedTextNode = textNode.splitText(result.index);
matchedText = result[0];
matchLength = matchedText.length;
textNode = (matchedTextNode.length > matchLength) ?
matchedTextNode.splitText(matchLength) : null;
surroundingNode = surrounderCreateFunc(matchedTextNode.cloneNode(true));
parent.insertBefore(surroundingNode, matchedTextNode);
parent.removeChild(matchedTextNode);
}
}
function updateKeywords() {
var savedSelection = rangy.saveSelection();
surroundInElement(editorEl, /\{\w+\}/, createKeyword);
rangy.restoreSelection(savedSelection);
}
function keyUpHandler() {
if (keyTimer) {
window.clearTimeout(keyTimer);
}
keyTimer = window.setTimeout(function() {
updateKeywords();
keyTimer = null;
}, keyDelay);
}
editorEl.onkeyup = keyUpHandler;
Related: