ajax无刷新评论功能

//去掉左右尖括号 并用去掉空格后的字符串替代显示 function replaceBrackets(id) {   var inputValue = $("#" + id).val();   while (inputValue.indexOf("<") != -1) {     inputValue = inputValue.replace("<", "[");   }   while (inputValue.indexOf(">") != -1) {     inputValue = inputValue.replace(">", "]");   }   while (inputValue.indexOf("&") != -1) {     inputValue = inputValue.replace("&", " ");   }   $("#" + id).val(inputValue); }  function replaceChar(name, char) {   var inputValue = $("#" + name).val();   while (inputValue.indexOf(char) != -1) {     inputValue = inputValue.replace(char, "");   }   return inputValue; }  $("#txtMessage").blur(function () {   $("#txtMessage").val(replaceChar("txtMessage", "<!--"));   if ($("#txtMessage").val() == "") {     document.getElementById("txtMessage").style.color = "#8C8C8C";     $("#txtMessage").val("没有填写留言内容");     return false;   }   replaceBrackets("txtMessage");   return true; });  $("#txtMessage").focus(function () {   if ($("#txtMessage").val() == "没有填写留言内容") {     document.getElementById("txtMessage").style.color = "#000000";     $("#txtMessage").val("");   } });  function txtanum(id, name)  //统计txta的输入字数 {   var maxl = 151;   var num = 150;   var content = $("#" + id).val();   content.slice(0, maxl);   var nowlength = content.length;   if (nowlength >= 0) {     if (nowlength < num)       $("#" + name).text(nowlength);     else       $("#" + name).text(num);   } else     $("#" + id).val(content.substring(0, maxl - 1));    if (nowlength == 0)     $("#" + name).text(0);    if (nowlength > num)     $("#" + id).val(content.substring(0, num)); }   var isSubmit = false; $('#subMessage').click(function () {    if (isSubmit) {     return;   }   isSubmit = true;   if ($("#txtMessage").val() == "没有填写留言内容" || $.trim($("#txtMessage").val()) == "") {     alert("请输入留言内容！");     isSubmit = false;     return;   }   $.ajax({     type: "POST",     url: app_param.path_context+"/user/member/msgboard/save",     data: { "context": ($("#txtMessage").val()) },     error: function () {       isSubmit = false;     },     success: function (data) {       if (data) {         addRow(data);         isSubmit=false;        $('#zanwu').hide();         document.getElementById("txtMessage").style.color = "#8C8C8C";     $("#txtMessage").val("没有填写留言内容");       }      }   });   function addRow(messageboard) {     var table = $("#tblmsg");     var html = [];     html.push("<tr>");     html.push("<td class='m_time'>");     html.push(messageboard.createDate);     html.push("</td>");     html.push("<td>");     html.push(messageboard.context);     html.push("</td>");     html.push("<td style='border-right: 0;' class='m_order_procz'>");     html.push("<a class='xxx' href='messagereply/"+messageboard.id+"'>查看</a>");     html.push("</td>");     html.push("</tr>");     html = html.join('');     table.append(html);   }  });