ajaxインプリメンテーションユーザー名が登録されているかどうか
5928 ワード
ajax ， ， ， ， ， servlet <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" > <html> <body> ： <input type= "text" /> ， <input type= "button" value= " " /> <hr/> <img height= "0" /> <script type= "text/javascript" > // " " ， document.getElementsByTagName( "input" )[ 1 ].onclick=function(){ var username = document.getElementsByTagName( "input" )[ 0 ].value; // ajax var xhr = createXHR(); //readyState ， xhr.onreadystatechange=function() { //ajax if (xhr.readyState== 4 ) { // ok if (xhr.status== 200 ) { // var msg = xhr.responseText; if (msg== "YES" ) { // var imgElement = document.images[ 0 ]; imgElement.setAttribute( "src" , "MsgSent.gif" ); imgElement.setAttribute( "height" , "40" ); } else { var imgElement = document.images[ 0 ]; imgElement.setAttribute( "src" , "MsgError.gif" ); imgElement.setAttribute( "height" , "40" ); } } } } var method = "POST" ; var url = "${pageContext.request.contextPath}/register?time=" + new Date().getTime(); var sendData = "username=" +username; xhr.open(method,url); xhr.setRequestHeader( "content-type" , "application/x-www-form-urlencoded" ); xhr.send(sendData); } // AJAX ( XMLHttpRequest) function createXHR(){ var xhr = null ; try { //IE xhr = new ActiveXObject( "microsoft.xmlhttp" ) } catch (e){ try { // IE xhr = new XMLHttpRequest(); } catch (e){ alert( " ， " ); } } return xhr; } </script> </body> </html> servlet, struts action.