I am checking some date whether available or not from DB using Ajax using below my code,
var url = "ValidateDateFromDB.jsp?cdate="+selecteddate.value;
if (window.XMLHttpRequest)
req = new XMLHttpRequest();
else if (window.ActiveXObject)
req = new ActiveXObject("Microsoft.XMLHTTP");
req.open("GET", url, true);
req.onreadystatechange =callback;
req.send(null);
function callback()
{
if (req.readyState == 4)
{
if (req.status == 200)
{
var message = req.responseText;
alert(message);
if(message.startsWith("Available"))
{
alert("Availabe");
}
else
{
alert("Not Availabe");
}
}
}
}
I am getting output like below image,
It is working fine in firefox but not working in chrome.I checked out that startsWith works only chrome above 40 version.So to fix this i used == operation like below,
if(message=="Available")
{
alert("Availabe");
}
else
{
alert("Not Availabe");
}
But this code always goes to else part that i know why.
someone tell me how to fix this?
Related
I am using ajax so that i can read the content of a file from my server .I am calling a function where ajax is , in a timer.And this is affecting my server .It is crashing.If this is the correct way to do it , what's wrong?
Please give a few sugestions,because i don't know what its problem is.
I am calling first the function:"function(ctrl)".
function get(ctrl){
var content;
content=ctrl.id;
var getTextUpdate= setInterval(function () {
readdocument();
}, 1200);
}
function readdocument() {
var xmlhttp;
if (window.XMLHttpRequest){
xmlhttp=new XMLHttpRequest();
}else{
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function(){
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("area").value=xmlhttp.responseText;
}
}
xmlhttp.open("GET","../user/test/read-text.php?user="+content,true);
xmlhttp.send();
}
Here it is the read-text.php file:
<?php
$rec_user=$_GET['user'];
echo($rec_user);
$chat = fopen($rec_user.".txt", "r") or die("Unable to open file!");
echo fread($chat,filesize($rec_user.".txt"));
fclose($chat);
?>
The problem with your code is that, you are not waiting for the response to get over. So over the time, you are sending request after request. This is going to use up all memory in due time. So first wait for the response before sending the next request.
How about this ?
function loadXMLDoc(ctrl) {
var content=ctrl.id;
var xmlhttp = new XMLHttpRequest();
var url = "../user/test/read-text.php?user="+content;
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == XMLHttpRequest.DONE) {
if (xmlhttp.status == 200) {
document.getElementById("area").value=xmlhttp.responseText;
setTimeout(loadXMLDoc(), 1200); //call the function again
} else if (xmlhttp.status == 400) {
console.log('There was an error 400');
} else {
console.log('something else other than 200 was returned');
}
}
};
xmlhttp.open("GET", url, true);
xmlhttp.send();
};
loadXMLDoc(ctrl);
function getXmlHttpRequestObject()
{
var xmlHttp = false;
if (window.XMLHttpRequest)
{
return new XMLHttpRequest(); //To support the browsers IE7+, Firefox, Chrome, Opera, Safari
}
else if(window.ActiveXObject)
{
return new ActiveXObject("Microsoft.XMLHTTP"); // For the browsers IE6, IE5
}
else
{
alert("Error due to old verion of browser upgrade your browser");
}
}
var xmlhttp = new getXmlHttpRequestObject(); //xmlhttp holds the ajax object
function servletPost()
{
if(xmlhttp)
{
var comp_to = document.getElementById("comp_to").value;
var comp_subject = document.getElementById("comp_subject").value;
var comp_letter = document.getElementById("comp_letter").value;
var date_time = document.getElementById("date_time").value;
if(comp_to==""||comp_subject==""||comp_letter==""||date_time=="")
{
document.getElementById("redSignal").style.display='block';
document.getElementById("redSignal").innerHTML="All Fields are necessary";
}
else
{
xmlhttp.open("POST","complaintHandler",true);
xmlhttp.onreadystatechange = handleServletPost;
xmlhttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
var data_string="to="+comp_to+"&subject="+comp_subject+"&complaint="+comp_letter+"&date_time="+date_time;
xmlhttp.send(data_string);
}
}
}
function handleServletPost()
{
if (xmlhttp.readyState == 4)
{
if(xmlhttp.status == 200)
{
document.getElementById("greenSignal").style.display='block';
document.getElementById("greenSignal").innerHTML=xmlhttp.responseText;
}
else
{
document.getElementById("redSignal").style.display='block';
document.getElementById("redSignal").innerHTML="Error Code ="+xmlhttp.status;
}
}
}
I am getting the problem of error code 404
What could be the problem in this code? Please help me.
Error 404 itself says that your URL is wrong .
xmlhttp.open("POST","complaintHandler-wrong",true);
check this URL 1st .
ERROR 404 Says. The requested Http request is not present or wrong.
Please check your "complaintHandler" It might be complaintHandler.jsp , kind of...
Please go through this tutorial for your future use.
Here is the scenario:
I have a text box where I can enter a text for "Status". Beside it is a label that should contain the latest "Status". After entering a new status, a button of type button is invoked and calls 2 things(a pop-up cor credentials and a function for XMLHttpRequest).
function a(url){
try {
if (window.XMLHttpRequest) {
req = new XMLHttpRequest();
} else if (window.ActiveXObject) {
req = new ActiveXObject("Microsoft.XMLHTTP");
}
if (req != null) {
req.open("GET", url, true);
req.onreadystatechange = getData;
req.send();
} else {
alert("fail");
}
} catch (e) {
alert("Error");
}
}
function getData(){
if(req.readyState == 4){
...some code
}
}
After entering credentiols and click on ok, the latest status should be updated. This is working fine in firefox and chrome. Also the only time the status updates on IE is when the browser was closed then opened.
I'm using this code below for the navigation system on my site, the purpose is to open an HTML page within a div .. (InnerHTML), but, when I'm clicking one of my menu links I'm getting the JavaScript notification "Problem: " (see "else" in the JavaScript code block). This code is fixed (good) for SEO aspect.
Can someone please tell me what the problem with it is? I'm trying to preserve the code as it is as much as possible.
Thank you in advance for your help!
JavaScript code:
function processAjax(url)
{
if (window.XMLHttpRequest) { // Non-IE browsers
req = new XMLHttpRequest();
req.onreadystatechange = targetDiv;
try {
req.open("GET", url, true);
}
catch (e) {
alert(e);
}
req.send(null);
} else if (window.ActiveXObject) { // IE
req = new ActiveXObject("Microsoft.XMLHTTP");
if (req) {
req.onreadystatechange = targetDiv;
req.open("GET", url, true);
req.send();
}
}
return false;
}
function targetDiv() {
if (req.readyState == 4) { // Complete
if (req.status == 200) { // OK response
document.getElementById("containerDiv").innerHTML = req.responseText;
} else {
alert("Problem: " + req.statusText);
}
}
}
In HTML body:
<a onclick="return processAjax(this.href)" href="example.html">CLICK ME</a>
<div id="containerDiv"></div>
The server returned a non-200 response. If you're using a debugger like Firebug, Chrome Developer, or IE Developer, check the Network tab to see exactly where your XHR went, and what the response was.
I am trying to send some parameters through xmlHttpRequest.send(params) written in a JS file to my servlet where I try to get the parameters by req.getParameter("some_Parameter"); it returns null on the servlet. though if i send the parameters by appending them in url it works fine. but when the url will be large it will break the code. so please someone help me out.
Thanks in advance.
function doHttpPost(theFormName, completeActivity)
{
var xmlhttp = new ActiveXObject("MSXML2.XMLHTTP");
var xmlMessage = buildPOST(theFormName, completeActivity);
var responseTxt;
try {
xmlhttp.Open(document.forms[theFormName].method, document.forms[theFormName].action+'?'+xmlMessage, false);
xmlhttp.onreadystatechange=function() {
if (xmlhttp.readyState==4) {
responseTxt = xmlhttp.responseText;
}
}
xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
enableDisableLinks(true);
setPointer();
xmlhttp.Send();
if(xmlhttp.Status != 200) {
alert("Post to server failed");
}
} catch (e) {
responseTxt = "Exception while posting form data: Error No: " + e.number + ", Message: " + e.description;
}
resetPointer();
enableDisableLinks(false);
var expectedTxt = "Form Data had been successfully posted to the database."
if(responseTxt.toString() == expectedTxt.toString()) {
// MNP: New requirement from Jeanne, should not refresh CM page, commenting it off for now
//if(completeActivity) {
// if (typeof (ViewCaseDetailBtn) != 'undefined') {
// ViewCaseDetailBtn.click();
// }
//}
return true;
} else {
alert (responseTxt);
}
return false;
}
BUGS
//IE only - shooting yourself in the
// Not all IE versions use ActiveX!
var xmlhttp = new ActiveXObject("MSXML2.XMLHTTP"); foot.
//JavaScript case sensitive, open !== Open
xmlhttp.Open(document.fo...
//JavaScript case sensitive, send !== Send
xmlhttp.Send();
//JavaScript case sensitive, status !== Status
xmlhttp.Status
AND if you are using synchronous, it does not call the onreadystatechange.
If you are using POST, the value needs to be in send("valuestosendup") not on the querystring.
This code shows why you should really use a framework to make Ajax calls and to not roll your own.