<!doctype html><html><head><meta charset="utf-8"><title>无标题文档</title></head> <body><script ??type="text/javascript"> ??function setCaret(textObj) { ???if (textObj.createTextRange) { ???????textObj.caretPos = document.selection.createRange().duplicate(); ???}}function insertAtCaret(textObj, textFeildValue) { ???if (document.all) { ???????if (textObj.createTextRange && textObj.caretPos) { ???????????var caretPos = textObj.caretPos; ???????????caretPos.text = caretPos.text.charAt(caretPos.text.length - 1) == ‘ ??‘ ? textFeildValue + ‘ ??‘ : textFeildValue; ???????} else { ???????????textObj.value = textFeildValue; ???????} ???} else { ???????if (textObj.setSelectionRange) { ???????????var rangeStart = textObj.selectionStart; ???????????var rangeEnd = textObj.selectionEnd; ???????????var tempStr1 = textObj.value.substring(0, rangeStart); ???????????var tempStr2 = textObj.value.substring(rangeEnd); ???????????textObj.value = tempStr1 + textFeildValue + tempStr2; ???????} else { ???????????alert("This ??version ??of ??Mozilla ??based ??browser ??does ??not ??support ??setSelectionRange"); ???????} ???}} ???</script> ???????<form ??id="form1" ??action="" ??onsubmit="" ??method="post" ??enctype="text/plain"> ?????<p> ???<textarea ??name="tarea" ??rows="" ??cols="" ??style="width:300px;height:120px;" ??onselect="setCaret(this);" ??onclick="setCaret(this);" ??onkeyup="setCaret(this);" ??>例子例子例子例子例子</textarea> ???<br/><br/> ???<input ??type="text" ??name="textfield" ??style="width:220px;" ??value="插入FireFox"/> ???<br/> ???<input ??type="button" ??value="插入" ??onclick="insertAtCaret(this.form.tarea,this.form.textfield.value);"/> ???</p> ???</form> ??<div id="box" contenteditable="true" style="border:1px solid #ccc; width:300px; height:200px;">sljfldjfldf</div> </body></html>推荐：http://www.cnblogs.com/huanlei/p/3242096.html
js实现在光标的位置 添加内容
原文地址：http://www.cnblogs.com/sghy/p/7462870.html