I have a PHP script that I'm calling with the .post() function in jQuery. If everything goes well, it outputs "WIN", otherwise it outputs whatever database errors or whatever else it gets.
$.post("myscript.php", {key: "value"}, function(data) {
if(data=="WIN") {
// the stuff that I want it to do that it won't do
} else {
alert(data);
}
});
When it runs however, I get "WIN" in a JS alert, and the stuff that I want it to do doesn't happen. Since "WIN" shows up in the alert, the PHP script is clearly outputting what I had expected. I had even made sure to set the Content-Type of the PHP script to text/plain, so why doesn't data=="WIN". Why does my WIN FAIL?
Have you checked for whitespace? Any whitespace before or after echo "WIN" will affect the output, also, check for whitespace before and after your <?php tags.
You are most likely trying to access the returned data from 'data' directly. Try
alert(data.d);
I think that you will find that the returned data is in a property. If I remember correctly, that property's name is 'd'. Use the FireFox plugin FireBug to view the returned data. It is very helpful for AJAX debugging.
Good Luck!
Related
I've been trying this for 3 days but couldn't find a solution yet. I need to load a php page with javascript. I'm using the code bellow however changing the page while the function is still working slows the page down.
$.post("connect.php?refresh_steamdata=true",{
},
function(data)
{
alert("loaded!");
});
load() is a simplified version of Post that replaces the contents of an element with the response from the server.
".load() sets the HTML contents of the matched element to the returned data."
$.post() will get you the result you are looking for but it does so Asynchronously. This means that if you plan to do something with the response you get back from the server you need to do it inside of the success function
$.post("<? echo $js_url."?refresh_steamdata=true"; ?>",{},function(data){
alert("loaded!");
// do something with data HERE
});
// not here since this will run before the data is returned
The Program I'm writing and the functionality I'm trying to achieve
Okay. So what I'm writing at the moment is a very simple forum, in Javascript using AJAX. Part of my task is to add a new post, using an API that my lecturer wrote for us in PHP. Just to note, the API and the SQL database are completely local.
The function I am using to add this post is:
function addPosts()
{
// Add the new thread to the SQLlite database.
var treq = new Request({
url:'guestbook/control.php?action=insertPost',
'method':'post',
onSuccess: function() {
alert('win');
},
onFailure: function() {
alert('fail');
}
}).send(Object.toQueryString({
// Had to convert it to a query string because it wouldn't work as a normal object.
// These are the required values to send, to store a "post" in the database.
'name':'This is a name',
'comment':'This is a comment!'
}));
}
I am aware this will add the same data every single time. I'm just trying to get the damn thing working!
The problem
What is happening is, when this function is called, I am getting an SQL syntax error. I was confused, because that would imply that my lecturer's code is wrong. After speaking with my lecturer, he explained that this happens when the post data isn't sent correctly to the PHP code. So I went about using Google Chrome's developer tools to see what was going on, and this is what I discovered:
Now to me, this means that the data is successfully being loaded into the request, and is being passed to the PHP files fine. Obviously I'm wrong. I've been racking my brains trying to make this work.
I know that the API works fine, because everyone else in my class isn't having any problem with it, and the code I am using is practically a rip off of the code in the notes, so I'm about 90% sure that's correct to.
One thing to note is that the code in the onSuccess key runs, so I know it's not a problem on the AJAX side.
Another thing is that this code worked in University on those computers, and it's since I've got it home that it's decided not to work.
Stack Trace
Fatal error: Uncaught exception 'PDOException' with message
'SQLSTATE[HY000]: General error: 1 near ")": syntax error' in G:\Ajax
Coursework\guestbook\php\database.php:134Stack trace:#0 G:\Ajax
Coursework\guestbook\php\database.php(134): PDO->prepare('INSERT INTO
pos...')#1 G:\Ajax Coursework\guestbook\php\class.GuestBook.php(44):
DatabaseHandler->insert(Array)#2 G:\Ajax
Coursework\guestbook\control.php(8): GuestBook->insert(Array)#3
G:\Ajax Coursework\guestbook\control.php(56): insertPost()#4 {main}
thrown in G:\Ajax Coursework\guestbook\php\database.php on line 134
Object.toQueryString is used in convert an object to a query string. So if the server is requiring both $_POST['name'] and $_POST['comment'] to be set, it wont be.
Frankly because you are posting it, I dont think $_GET['name'] or $_GET['comment'] would be set either.
Request.send expects an opject. You are sending it a string. So it should be
Request.send({prop: 'value'}), not Request.send(value).
Do yourself a favor and make a PHP with the following php code, and see what it returns. It may clear this up for you right away. I have a feeling nothing is being sent except for $_GET['action']
<?php
echo '<pre>';
print_r($_GET);
print_r($_POST);
echo '</pre>';
?>
Just in-case anyone stumbles upon this thread looking for an answer:
function addPosts()
{
// Add the new thread to the SQLlite database.
var treq = new Request({
url:'guestbook/control.php?action=insertPost',
onSuccess: function() {
alert('win');
},
onFailure: function() {
alert('fail');
}
}).post('name=This is a name&comment=This is a comment!');
}
Here I'm using the .post method to POST data.
I have been struggling since yesterday with the following piece of code.
function findLocation(){
alert(1);
$.getJSON( "http://www.omc4web.com/geoip/geoip.php",
{ip: "127.0.0.1",
callingurl: "www.thissite.com" },
function( result ){
alert(2);
$.each(result, function(i, field)
{
alert(i);
if(i=="country")
{
country_code = field;
}
});
})
}
It does not seem to want to get beyond the calling of the php script. The returned data is {"country":"US","store":"US"} but the function does not seem to want to process it and I never get to alert(2). I have placed monitors in the php script and I can see that it does indeed get called with the correct parameters and it does return the data expected.
if you call http://www.omc4web.com/geoip/geoip.php?ip=127.0.0.1&callingurl=www.thissite.com from your browser you will see that data is returned.
The same piece of code calling a URL with no parameters behaves correctly, but not with the above setup.
My few remaining hairs would appreciate some help on this.
additional info:
header('Content-type: application/json'); set on php script
tried it on chrome and firefox
no errors show up on firebug just a blank response screen
running script from localhost, but if its a cross domain issue, why am I able to make a similar call (without params) to amazon? $.getJSON("http://freegeoip.net/json/",function(result){ works fine as does the popular flickr example.
I am using <script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
Thanks in advance
Ossi
I think it's a cross domain issue. I guess you're able to use freegeoip.net because you're using JSONP. Try looking at the jQuery documentation to learn how to use JSONP: jQuery.getJSON()
I am using $.post to load some js code from a MYSQL database. How do I execute it?
You can use $.ajax (instead of $.post) with the the dataType option set to script:
"script": Evaluates the response as JavaScript and returns it as plain text. Disables caching unless option "cache" is used. Note: This will turn POSTs into GETs for remote-domain requests.
$.eval = function(str) {
eval(str);
}
$.fn.eval = function(str) {
eval(this.selector);
}
$.post(url, function(data) {
$.eval(data);
//$(data).eval();
});
Jokes aside. You can use eval to run a snippet of JavaScript. I'm sure everyone else will tell you why eval is evil.
Ideally though what your doing is bad. There's a far better way to solve your problem that doesn't involve grabbing code from a database.
Here's some simple Javascript:
(function($){
var ajax_callback = function(data) { window.location.hash = data.h1; };
$('.clickable').live('click', function() {
$.post('server.fcgi', {}, ajax_callback, 'json');
}
);
})(jQuery);
The server is a c++ binary (yes, i know) that spits out (through fast_cgi) the string:
{"h1":"newhash"}.
The expected behavior is that the URL should change.
Instead, nothing happens and Firebug complains that 'data' is "null"!.
Any help would be greatly appreciated!
Will.
When the following code enters "ajax_callback", it says that "data" is "null"!.
But the server is a c++ binary that is confirmed to return the JSON string {"h1":"newhash"}.
Anyone have an idea why JQuery seems unable to accept the JSON data when calling the ajax_callback?
I did have similar problem as you have mentioned when using $.POST().
There are two things if you are using jquery $.post method. You need to add an extra bracket before defined data type ("JSON") as shown below. I don't know why but it works, it will return data.
$.post('server.fcgi', {}, ajax_callback,{}, 'json');
The second thing is that you will need to parse JSON data using $.parseJSON(data) in side the callback function.
One more thing to make sure that the url to fetch JSON, the page document type should be defined as JSON in the header.
I have given an example below.
$.post("url/path/here/to/json", {}, function(data){
if(data){ // just in case the called program had a problem
var obj = $.parseJSON(data);
.... do everything else using the Obj->
}
},{},"json");
This will work.
However I recommend to you to use another Jquery function specially implemented for JSON, that is called
$.getJSON();
Here is the url for more information
And I am suggesting you to use the following method instead of the one described by you.
$(document).ready(function(){
$('.clickable').live('click', function() {
$.getJSON('server.fcgi', function(data){
window.location.hash = data.h1;
});
}
);
});
Make sure the server also returns the correct HTTP headers before the payload. E.g.:
HTTP/1.0 200 OK
Content-Type: application/json
Content-Length: ...
...
{"h1":"bla"}
From your description, I could not quite make out if all it did was printf("{\"h1\":\"bla\"}"); or not.
To check the actual result, use a command line tool like HEAD, GET, wget, curl, or even nc. If you are not able to use one of those, you might get some clues from the Net panel in Firebug and the like.
Probably not the answer you want to hear, but I assume you're using jQuery 1.4.2? I noticed that this does work as expected in 1.3.2 so you might want to consider using that instead. :(