function IsSwap()
{
var urlString = "<%= System.Web.VirtualPathUtility.ToAbsolute("~/mvc/Indications.cfc/GetModelType")%>";
var id =
{
id : GetGUIDValue()
}
$.ajax({
type: "POST",
url: urlString,
data: id,
success: function(data) {
if (data.toString() == 'SwapModel')
{
return true;
}
}
});
Expected result is true. I can alert right before the return so I know it's getting to that point fine. In another function, I tried to get my bool and use it like this:
var isSwap = IsSwap();
if (isSwap)
and it keeps saying isSwap is undefined. Why?
You are using ajax requests, which are asynchronous. You can't return value from an ajax request. Try this instead:
function IsSwap()
{
var urlString = "<%= System.Web.VirtualPathUtility.ToAbsolute("~/mvc/Indications.cfc/GetModelType")%>";
var id =
{
id : GetGUIDValue()
}
$.ajax({
type: "POST",
url: urlString,
data: id,
success: function(data) {
if (data.toString() == 'SwapModel')
{
ResultIsTrue(); // call another function.
}
}
});
After execution, instead of using this:
var isSwap = IsSwap();
if (isSwap){
// Do Somethinh
}
Try that:
IsSwap();
function ResultIsTrue(){
// Do Same Thing
}
You can't return from an ajax call like that.
Essentially what you're doing is returning true from the inner function.
You should just call whatever code you need in the success method as that's the only time you can guarantee that the ajax call has completed.
The AJAX request is asynchronous, meaning that IsSwap will return before the response to the AJAX request.
Whatever you need to do based on isSwap, you should do in the success handler of your AJAX request.
UPDATE: This last paragraph is incorrect about it working, but worth noting about synchronous not being recommended:
Alternatively, you could make the AJAX request synchronous (by adding async:false to the AJAX options) and keep it how you have it - however I wouldn't recommend this as your browser will 'freeze' whilst it waits for the response.
Check this line:
var urlString = "<%= System.Web.VirtualPathUtility.ToAbsolute("~/mvc/Indications.cfc/GetModelType")%>";
Try using single quotes like so:
var urlString = '<%= System.Web.VirtualPathUtility.ToAbsolute("~/mvc/Indications.cfc/GetModelType")%>';
Your double quotes inside double quotes is most likely your problem.
Related
I have an issue with a method ive created for an object ive created. one of the methods requires a callback to another method. the problem is i cant add the data to the object that called the method. it keeps coming back as undefined. otherwise when i send the data to the console it is correct. how can i get the data back to the method?
var blogObject = new Object();
var following = [...];
//get posts from those blogs
blogObject.getPosts = function () {
var followersBlogArray = new Array();
for (var i = 0; i < this.following.length;i++){
var followersBlog = new Object();
// get construct blog url
var complete_blog_url = ...;
i call the getAvatar function here sending the current user on the following array with it.
followersBlog.avatar = blogObject.getAvatar(this.following[i]);
that part goes smoothly
followersBlogArray.push(followersBlog);
}
this.followersBlogArray = followersBlogArray;
}
here is the function that gets called with the current user in following array
this function calls an ajax function
blogObject.getAvatar = function (data) {
console.log("get avatar");
var url = "..."
this ajax function does its work and has a callback function of showAvatar
$(function() {
$.ajax({
type: "GET",
dataType: "jsonp",
cache: false,
url: url,
data: {
jsonp:"blogObject.showAvatar"
}
});
});
}
this function gets called no problem when getAvatar is called. i cant however get it to add the data to the followersBlog object.
blogObject.showAvatar = function (avatar) {
return avatar
}
everything in here works fine but i cant get the showAvatar function to add to my followersBlog object. ive tried
blogObject.showAvatar = function (avatar) {
this.followersBlog.avatar = avatar;
return avatar
}
that didnt work of course. it shows up as undefined. can anyone help?
so somethings like...
$(function() {
$.ajax({
type: "GET",
dataType: "jsonp",
cache: false,
url: url,
complete: function () {
this.avatar = data;
}
data: {
jsonp:"blogObject.showAvatar"
}
});
});
}
Welcome to the world of asynchronous programming.
You need to account for the fact that $.ajax() will not return a value immediately, and Javascript engines will not wait for it to complete before moving on to the next line of code.
To fix this, you'll need to refactor your code and provide a callback for your AJAX call, which will call the code that you want to execute upon receiving a response from $.ajax(). This callback should be passed in as the complete argument for $.ajax().
The correct option for setting the JSONP callback is jsonpCallback. The recommendation from the API for .ajax(...) is to set it as a function.
{
// ...
jsonpCallback: function (returnedData) {
blogObject.showAvatar(returnedData);
},
// ...
}
I'm trying to fire an Ajax request with some data being returned by a function call and, as far as I can tell, the Ajax call isn't waiting for my function call to return.
I'm calling getSelectedMessages to get the values of a variable number of checkboxes before firing an Ajax request with an array of the values returned by getSelectedMessages.
getSelectedMessages looks like this:
var getSelectedMessages = function() {
var selected = [];
$('input:checkbox[name=multipleops]:checked').each(function() {
selected.push($(this).attr('value'));
});
return selected;
}
And the Ajax request that's invoking it looks like this:
$.ajax({
type: "POST",
url: "/api/messages/",
data: { ids: getSelectedMessages(), folder: folder },
cache: false,
success: function(){ location.reload() }
});
I've done a little bit of searching around and all I'm turning up are answers on how to return a value from a call and to it.
use
beforeSend attribute with ajax
try
var getSelectedMessages = function() {
var selected = [];
$('input:checkbox[name=multipleops]:checked').each(function() {
selected.push($(this).attr('value'));
});
return selected;
}
$.ajax({
type: "POST",
url: "/api/messages/",
beforeSend : function () { return jQuery.isEmptyObject(getSelectedMessages); }
data: { ids: getSelectedMessages(), folder: folder },
cache: false,
success: function(){ location.reload() }
});
Reference
beforeSend
isEmptyObject
Call getSelectedMessages() outside the ajax function of jquery (?)
The function is executed before the request is sent.
The real problem is that the getSelectedMessaged() returns an array.
This results in undefined=undefined after serialization in jQuery's internals.
And that gets ignored by the $.ajax(), so it looks like it's not sending in your vars but it's ignoring them because they're undefined.
If you concatenate a string with the values and make it a query string parameter yourself it should work.
I assume you want to send something like ?var[]=something&var[]=somethingelse to the server, so it ends up in PHP as an array?
Than you'll have to build up the string yourself in the getSelectedMessages function.
Hope it helps,
PM5544
Here is a function that I have to write to an xml file through an ajax call. The code works fine the first time the ajax call is made. On the second each loop, the ajax call isn't made at all. I don't know why. I specified asyn to false. That did not help. That doesn't seem to be the problem anyway.
$('#'+divid).children('div').children('div').each(function () {
var url = $(this).find('a');
var urlname = url.text();
var urllink = url.attr('href');
var urlid = $(this).attr('id');
alert ("from javascript urlid: "+urlid+" urlname: "+urlname+" urllink: "+urllink);
$.ajax({
url: "add_url.php",
type: "POST",
data: { nodeid: divid, urlid: urlid, urlname: urlname, urllink: urllink },
cache: false,
async: false,
success: function (response) {
if (response != '')
{
alert(response);
}
}
});
});
This really works for me
http://jsfiddle.net/genesis/DTjZQ/4 (3 POST request sent with response status 404)
be sure that your html is good and with same structure as in my fiddle
Instead of making multiple AJAX requests, I suggest appending the data to an array and then sending the entire array of objects.
(Basically the literal object you're using for data would be appended to an array instead of used in a request, and then once the each is done, you would send the array as the data.)
Ive been struggling to pass my parameters from a functions but I just really can't figure out where did I go wrong. I have a function that have a parameters that I want to pass to my postData to display datas in my jQgrid. Here's my function code with parameters:
function getTID(hdrID){
var selected = $('#editTallyHdr').val();
var hdrID = '';
var hdrNo = '';
var nameFlag=0;
var par_ams = {
"SessionID": $.cookie("SessionID"),
"dataType": "data"
};
$.ajax({
type: 'GET',
url: 'processjson.php?' + $.param({path:'getData/tallyHdr',json:JSON.stringify(par_ams)}),
dataType: primeSettings.ajaxDataType,
success: function(data) {
if ('error' in data)
{
showMessage('ERROR: ' + data["error"]["msg"]);
}
else{
$.each(data['result']['main']['rowdata'], function(rowIndex, rowDataValue) {
$.each(rowDataValue, function(columnIndex, rowArrayValue) {
var fldName = data['result']['main']['metadata']['fields'][columnIndex].name;
if (fldName == 'transaction_id'){
hdrID = rowArrayValue;
}
if (fldName == 'transaction_num'){
hdrNo = rowArrayValue;
if(selected == hdrNo){
nameFlag =1;
};
}
});
});
}
}
});
return (hdrID);
}
and here is my jQgrid code where I call that function to get it's parameter:
$("#tblPlank").jqGrid({
url: '',
datatype: 'local',
jsonReader : {
.
.
.
serializeGridData: function(postData) {
var ctr =0;
var filt=[];
var c=[];
var jsonParams = {
'SessionID': $.cookie("SessionID"),
'dataType': 'data',
'transaction_id':getTID(hdrID),
'filters': c,
'lines':plank_data,
'recordLimit': postData.rows,
'recordOffset': postData.rows * (postData.page - 1),
'rowDataAsObjects': false,
'queryRowCount': true,
'sort_fields': postData.sidx
};
.
.// some code here
.
.
return 'json=' + JSON.stringify(jsonParams);
},
loadError: function(xhr, msg, e) {
showMessage('HTTP error: ' + JSON.stringify(msg) + '.');
},
colNames:[...],
colModel:[
........................
],
.
.
.
caption: "Tally Transaction Details/Lines"
I also have another code where I want to get that parameter. Here's the last code:
var par_ams = {
"SessionID": $.cookie("SessionID"),
"dataType": "data",
"transaction_id": getTID(hdrTID)
}
$('#tblPlank').setGridParam({
url:'processjson.php?path=' + encodeURI('getData/tallyLnDtl') + '&json=' + encodeURI(JSON.stringify(par_ams)),
datatype: primeSettings.ajaxDataType,
});
$('#tblPlank').trigger('reloadGrid');
Those codes below that function getTID(hdrID) cant retrieve the parameter, it shows empty. This maybe simple to anyone, but I really need help on this.. been working with this for quite long hours.
This is a very common misunderstanding. I've probably answered 15 of these questions in the last two weeks alone. An ajax call is an asynchronous call. That means that when you make the ajax call, it just STARTs the request. Then, while that request goes in the background, your code immediately keeps executing. That means that your function getTID() returns before the ajax call has even completed and it's value is not yet known. Thus, there is no way to return the response value from the ajax function when you return from getTID() as it is simply not known yet.
To work with asynchronous function calls (like ajax calls), you have to change your programming style to something that works asynchronously. In this case, the response to your ajax call is ONLY known in the success handler for the ajax all. So, you have to restructure your code to continue on with the execution of your processing and the handling of the ajax response from the success handler. If you have only a little bit of work to do, then you can put it all in the success handler. If you have a lot of work to do, then you can put all the rest of that work in a function call and call it from the success handler.
The problem is that you're doing an ajax-request (asynchronous request). Then the function does not wait for an answer to arrive, but just continues and returns hdrID (which isn't set at the time). After that a response comes in, and the success-method is called, which sets hdrID to the appropiate value.
The common way to solve this is to execute a specific function with the desired values when the success-method is executed. It's too much code to look into, but it could go something like this:
function fetchContent(continueFunction) {
$.ajax(params).success(function(reply) {
// retrieve desired params from reply
continueFunction(retrievedParameters);
}
}
What you could do is define getTID to take in a callback to execute once it has the id, for instance
function getTID(hdrID, callback) {
//ajax stuff....
success: function (data) {
// Error checks, etc
hdrID = //something dependent on data
callback(hdrID); // THIS IS THE IMPORTANT PART
}
the callback will execute after the request has returned, when it is safe to use the data returned from the ajax request that will be needed in the callback. You could wrap all of the code that needs the return value of the request in the callback, for example
getTID(hdrID, function (ID) {
var params = {
"SessionID": $.cookie("SessionID"),
"dataType": "data",
"transaction_id": ID //USE ID
}
$('#tblPlank').setGridParam({
url:'processjson.php?path=' + encodeURI('getData/tallyLnDtl') + '&json=' + encodeURI(JSON.stringify(par_ams)),
datatype: primeSettings.ajaxDataType,
});
$('#tblPlank').trigger('reloadGrid');
};
});
I have this function that embeds flash :
function embedswfile(target, swf, base, width, height) {//dosomething}
And I want to call the function like this
embedSwf("flashgame",decode("<?=base64_encode($path['location'])?>"),decode("<?=base64_encode($path['base_directory'])?>"),"800","600" )
The idea is that whenever someone looks for any swf inside my website,he wont find anything clean.I will change the encoding algorithm,but this is just temporary. In order for that function to work,whenever I call the function 'decode' it must return a single value. PHP contains
<?php
echo base64_decode($_POST['s']);
?>
I tried this but it still wont work
var globvar;
function processdata(newmsg) {
globvar = newmsg;
}
function decode(s){
$.ajax({type: "POST",
url: "includes/decode.inc.php",
data: "s=" + s,
success:function(newmsg){
processdata(newmsg);
}
});
return globvar;
}
Important:
Forget about using Ajax and encoding, decoding the path. What do you think you gain from it? Security? No. One can figure out that this is bas64 encoded or he just monitors the network traffic and reads the response from the Ajax call.
Just do
embedSwf("flashgame","<? =$path['location']?>"),"<?=$path['base_directory']?>","800","600" )
Really, you cannot prevent someone else seeing the data and are just making things more complicated for you.
(Or you have to decrypt the data with JavaScript.)
(original answer is still correct nevertheless)
Ajax is asynchronous so something like var test = decode(s); will never work. The decode function will return before the Ajax call finishes.
Instead, put your logic into the callback handler. For example, if your code was this before:
var retdata = decode('s');
// here comes code that handles retdata
put the code into a function and call it from the success handler:
function process(retdata) {
// here comes code that handles retdata
}
function decode(s){
$.ajax({type: "POST",
url: "includes/decode.inc.php",
data: "s=" + s,
success:function(newmsg){
process(newmsg);
}
});
}
This seems to be a very common problem to all beginners. You will find a lot of questions here that deal with the same problem.
Update:
It is not nice, but you could change the function to
function decode(s, cb){
$.ajax({type: "POST",
url: "includes/decode.inc.php",
data: "s=" + s,
success:function(data){
cb(data);
}
});
}
and do
decode("<?=base64_encode($path['location'])?>", function(location) {
decode("<?=base64_encode($path['base_directory'])?>", function(dir) {
embedSwf("flashgame",location,dir,"800","600" );
});
});
Update 2:
For completeness, you can make the Ajax call synchronous, by using async: false. Then this will work:
function decode(s){
var ret;
$.ajax({type: "POST",
url: "includes/decode.inc.php",
data: "s=" + s,
async: false,
success:function(newmsg){
ret = newmsg;
}
});
return sync;
}
var val = decode(s);
However, this will block the browser until the Ajax call finished. You have to test whether this matters in your case or not.
Update 3:
You could also change your PHP script to not only accept one parameter but several and process both strings in one go.