asp.net Ajax之無刷新評論介紹

head runat="server">
title>/title>
script type="text/javascript">
var objXmlHttp = null;
function CreateXMLHTTP() {
if (window.ActiveXObject) {
objXmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
} else {
if (window.XMLHttpRequest) {
objXmlHttp = new XMLHttpRequest();
} else {
alert("初始化XMLHTTP錯誤！");
}
}
}
function DoComments() {
var data = "txtComments" + document.getElementById("txtComment").value;
CreateXMLHTTP();
objXmlHttp.open("POST", "DealComments.ashx", true);
objXmlHttp.onreadystatechange = function () {//在服務(wù)器響應(yīng)后調(diào)用
if (objXmlHttp.readyState >= 4) {
if (objXmlHttp.status == 200) {
var result = objXmlHttp.responseText;//獲得服務(wù)器返回的字符串
if (result == "true") {
var cTable = document.getElementById("commentTable");//獲得評論的表格對象
var newRow = cTable.insertRow(cTable.rows.length);//在表格的最后一行再添加一行
var cTd = newRow.insertCell();//在新添加的行中再添加一列
cTd.innerHTML = document.getElementById("txtComment").value;//設(shè)置列內(nèi)容為剛發(fā)布的評論內(nèi)容
} else {
alert("objXmlHttp.status");
}
}
}
}
objXmlHttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded"); //添加自定義HTTP頭道請求
objXmlHttp.send(data);//發(fā)送請求到服務(wù)器
}
/script>
/head>
body>
評論信息：
table id="commentTable" style="width: 600px; border: 1px solid #000;" border="1"
cellpadding="0" cellspacing="0">
tr>
%--td width="30%" class="style1">用戶名/td>--%>
td>
內(nèi)容
/td>
/tr>
/table>
br />
hr />
table style="width: 700px; border: 1px solid #000; text-align: left;" border="1"
cellpadding="0" cellspacing="0">
tr>
td>
發(fā)布內(nèi)容：
/td>
/tr>
tr>
td>
textarea id="txtComment" cols="60" rows="10">/textarea>
/td>
/tr>
tr>
td>
input type="button" onclick="DoComments()" id="btnComment" value="發(fā)布評論" />
/td>
/tr>
/table>
/body>
/html>

public void ProcessRequest(HttpContext context)
{
string strComment = context.Request.Form["txtComments"];//獲得傳過來的內(nèi)容
if (string.IsNullOrEmpty(strComment))//如果不為空，返回ture
{
context.Response.Write("true");
}
else
{
context.Response.Write("false");
}
context.Response.End();
}