ajax实例

<html>

                <head>

                           <title>AJAX实例</title>

                           <script language="javascript" type="text/javascript">    
                           <!--

                                     var xmlHttpRequest;  //定义一个变量用于存放XMLHttpRequest对象
                                     //定义一个用于创建XMLHttpRequest对象的函数（创建一个异步调用对象）
                                     function createXMLHttpRequest()
                                    {
                                            if(window.ActiveXObject)
                                            {
                                                   //IE浏览器的创建方式
                                                   xmlHttpRequest = new ActiveXObject("Microsoft.XMLHTTP");
                                            }else if(windew.XMLHttpRequest)
                                           {
                                                  //Netscape等其他浏览器中的创建方式
                                                  xmlHttpRequest = new XMLHttpRequest();
                                            }
                                   }
                                   //响应HTTP请求状态变化的函数
                                   function httpStateChange()
                                   {
                                          //判断异步调用是否完成
                                         if(xmlHttpRequest.readyState == 4)
                                        {
                                                //判断异步调用是否成功,如果成功开始局部更新数据；若html文件在服务器运行是200；若在本地是0；
                                                if(xmlHttpRequest.status == 200||xmlHttpRequest.status == 0)
                                                {
                                                       //查找节点
                                                       var node = document.getElementById("myDIv");

                                                        //更新数据

                                                        node.firstChild.nodeValue = xmlHttpRequest .responseText;
                                                }
                                                else
                                               {
                                                     //如果异步调用未成功,弹出警告框,并显示出错信息
                                                     alert("异步调用出错/n返回的HTTP状态码为:"+xmlHttpRequest.status + "/n返回的HTTP状态信息为:" + xmlHttpRequest.statusText);
                                               }
                                         }
                                     }
                                    //异步调用服务器段数据
                                   function getData(name,value)
                                  {                   
                                       //创建XMLHttpRequest对象
                                       createXMLHttpRequest();
                                       if(xmlHttpRequest!=null)
                                       {
                                            //创建HTTP请求
                                            xmlHttpRequest.open("get","ajax.text",true)
                                           //设置HTTP请求状态变化的函数
                                            xmlHttpRequest.onreadystatechange = httpStateChange;
                                           //发送请求
                                          xmlHttpRequest.send(null);
                                        }
                                  }

                           -->
                          </script>

                </head>

                <body>

                         <div id="myDiv">原数据</div>

                         <input type = "button" value = "更新数据" onclick = "getData()">

                </body>

       </html>

 

posted @ 2019-04-22 15:22  认真对待生活  阅读(114)  评论(0)    收藏  举报