<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Document</title> </head> <body> <button type="button" onclick="document.getElementById(‘test‘).focus(); insertHtmlAtCaret(‘<b>INSERTED</b>‘);">插入字符</button> <div contentEditable="true" style="height:50px; border:2px solid red;" id="test"> </div> <script> function insertHtmlAtCaret(html) { var sel, range; if (window.getSelection) { // IE9 and non-IE sel = window.getSelection(); if (sel.getRangeAt && sel.rangeCount) { range = sel.getRangeAt(0); range.deleteContents(); // Range.createContextualFragment() would be useful here but is // non-standard and not supported in all browsers (IE9, for one) var el = document.createElement("div"); el.innerHTML = html; var frag = document.createDocumentFragment(), node, lastNode; while ( (node = el.firstChild) ) { lastNode = frag.appendChild(node); } range.insertNode(frag); // Preserve the selection if (lastNode) { range = range.cloneRange(); range.setStartAfter(lastNode); range.collapse(true); sel.removeAllRanges(); sel.addRange(range); } } } else if (document.selection && document.selection.type != "Control") { // IE < 9 document.selection.createRange().pasteHTML(html); } } </script> </body> </html>
原文：http://www.cnblogs.com/kongxs/p/4128208.html