AjaxOperations.aspx.cs

using System; using System.Collections.Generic; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Xml; namespace WebTest2008 { public partial class AjaxOperations : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { if (!string.IsNullOrEmpty(Request["action"]) && Request["action"] == "xmlOp") // 处理xml { XmlDocument doc = new XmlDocument(); try { doc.Load(Request.InputStream); //获取xml数据(这里需要注意接受xml数据的方法) } catch (Exception ex) { throw ex; } string responseTxt = ""; string tempName = doc.SelectSingleNode("profile/userName").InnerText; string tempPwd = doc.SelectSingleNode("profile/userPwd").InnerText; if (tempName == "test" && tempPwd == "test") { responseTxt = "验证通过！"; } else responseTxt = "验证失败！"; Response.Write(responseTxt); // 写文本 } } } }

很简单的代码，运行看看吧。

2、接收XML数据：

我们看到，上面两个.js文件里处理返回数据时都用到了xmlReq.responseText的属性，下面我们试试看xmlReq.responseXML属性：

testJs.js

// 此函数等价于document.getElementById /document.all function $(s) { if (document.getElementById) { return eval('document.getElementById("' + s + '")'); } else { return eval('document.all.' + s); } } // 创建 XMLHttpRequest对象，以发送ajax请求 function createXMLHTTP() { var xmlHttp = false; var arrSignatures = ["MSXML2.XMLHTTP.5.0", "MSXML2.XMLHTTP.4.0", "MSXML2.XMLHTTP.3.0", "MSXML2.XMLHTTP", "Microsoft.XMLHTTP"]; for (var i = 0; i < arrSignatures.length; i++) { try { xmlHttp = new ActiveXObject(arrSignatures[i]); return xmlHttp; } catch (oError) { xmlHttp = false; //ignore } } // throw new Error("MSXML is not installed on your system."); if (!xmlHttp && typeof XMLHttpRequest != 'undefined') { xmlHttp = new XMLHttpRequest(); } return xmlHttp; } var xmlReq = createXMLHTTP(); // 发送ajax处理请求(这里简单验证用户名和密码的有效性，默认正确的输入：用户名和密码都是test) function validatePwd(oTxt) { var url = "/AjaxOperations.aspx?action=xmlOp"; var xmlStr = "<profile>" + " <userName>" + escape($("txtUserName").value) + "</userName>" + " <userPwd>" + escape($("txtPwd").value) + "</userPwd>" + "</profile>"; xmlReq.open("post", url, true); // Tell the server you're sending it XML xmlReq.setRequestHeader("Content-Type", "text/xml"); xmlReq.onreadystatechange = callBack; xmlReq.send(xmlStr); // 发送XML } function callBack() { if (xmlReq.readyState == 4) { if (xmlReq.status == 200) { var xmlDoc = xmlReq.responseXML; // 接收XML // var nodes = xmlDoc.childNodes; // alert("文件根标签的名称： " + xmlDoc.documentElement.tagName); // alert("根元素共有子节点个数: " + xmlDoc.documentElement.childNodes.length); alert(xmlDoc.documentElement.childNodes(0).text); } else if (xmlReq.status == 404) { alert("Requested URL is not found."); } else if (xmlReq.status == 403) { alert("Access denied."); } else alert("status is " + xmlReq.status); } }

同样，jsTest.htm文件不变，AjaxOperations.aspx的HTML文件内容不变，服务器端.CS处理代码稍作修改如下：

using System; using System.Collections.Generic; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Xml; namespace WebTest2008 { public partial class AjaxOperations : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { if (!string.IsNullOrEmpty(Request["action"]) && Request["action"] == "xmlOp") // 处理xml { XmlDocument doc = new XmlDocument(); try { doc.Load(Request.InputStream); //获取xml数据 } catch (Exception ex) { throw ex; } string responseXmlTxt = ""; string tempName = doc.SelectSingleNode("profile/userName").InnerText; string tempPwd = doc.SelectSingleNode("profile/userPwd").InnerText; if (tempName == "test" && tempPwd == "test") { responseXmlTxt = "<?xml version=\"1.0\" encoding=\"utf-8\" ?> <msg>验证通过！</msg>"; // 测试用，简单的xml文件 } else responseXmlTxt = "<?xml version=\"1.0\" encoding=\"utf-8\" ?><msg>验证失败！</msg>"; Response.ContentType = ("text/xml;charset=UTF-8"); // 这里必须要设置，否则客户端接收不到这里写好的xml文件 Response.Write(responseXmlTxt); // 写xml Response.End(); } } } }

好了，前面两种方法是大家平时开发中比较熟悉的方式，下面我们来看看第三种方式。

三、JSON方式

json的准备知识：