This is my first time, that I am working with json.
This is the situation:
I get data via php from my mysql database and store this into a php array:
$statement = $mysqli->prepare("SELECT chatToken, lastMessageID FROM chat")
$statement->execute();
$result = $statement->get_result();
while($row = $result->fetch_object()) {
$chatData[$row->chatToken] = $row->lastMessageID;
}
Now I would like to get this in a jquery function:
I tried this:
var chatData = '<? echo json_encode($chatData); ?>'
myFunction(chatData)
function myFunction(chatData) {
console.log(chatData)
// OUTPUT: {"tgv5pxfjsDGXA3JcEYVM":88,"a9gxNZ7HzfcJXQsWCtAp":99}
$.ajax({
type: "POST",
url: "getData.php",
data: 'chatData='+chatData,
dataType: 'json',
}).done(function(result) {
console.log(result);
// Please look the Picture below for output
})
}
Output of console.log(result)
getData.php
<?php
$chatData = json_decode($_POST['chatData']);
$message = array();
foreach($chatData AS $chatToken => $lastMessageID) {
$statement = $mysqli->prepare("SELECT * FROM `messages` WHERE `chatToken` = ? AND `ID` > ?")
$statement->bind_param("ss", $chatToken, $lastMessageID);
$statement->execute();
$result = $statement->get_result();
while($row = $result->fetch_object()) {
$message[] = array(
"lastMessageID" => $row->ID,
"chatToken" => $row->chatToken,
);
}
$statement->close();
}
echo json_encode($message);
?>
So far so good.
But now I would like to replace / update my var chatData:
{"tgv5pxfjsDGXA3JcEYVM":88,"a9gxNZ7HzfcJXQsWCtAp":99}
with values from the result. Finally it have to be:
{"tgv5pxfjsDGXA3JcEYVM":188,"a9gxNZ7HzfcJXQsWCtAp":99}
How can I realize it?
As chatData is JSON (a string), you can:
parse it into an object JSON.parse
make the change
convert it back to a string JSON.stringify
// result from ajax call, jquery converts this from the php json to an object/array
var result = [{chatToken:"tgv5pxfjsDGXA3JcEYVM",lastMessageID:188}];
// string from `var chatData = <?php ...` as JSON
var chatData = '{"tgv5pxfjsDGXA3JcEYVM":88,"a9gxNZ7HzfcJXQsWCtAp":99}';
// convert string to object
var data=JSON.parse(chatData);
// use the first result array ([0]) chatToken to update chatData
data[result[0].chatToken] = result[0].lastMessageID;
// convert back to JSON (string)
chatData = JSON.stringify(data);
// show result
console.log(chatData);
In your case, I'd recommend converting chatData to an object at the start
var chatData = JSON.parse('<? echo json_encode($chatData); ?>');
and then using it as an object, then convert to json(string) only as needed (in the ajax post)
data: 'chatData='+JSON.stringify(chatData),
Im retrieving an array from php file called check_num.php :-
check_num.php
<?php
include 'config.php';
session_start();
$VALUE = $_SESSION["some_session_variable"];
if(isset($_POST['default'])){
$ert = "SELECT * FROM table_name WHERE something = '$VALUE' ORDER BY p_id ASC ";
$qty = mysql_query($ert);
$fgh = mysql_num_rows($qty);
$ertz = "SELECT something, COUNT(something) FROM table_name WHERE something = '$VALUE'
AND something >= 1 GROUP BY p_id ORDER BY p_id ASC";
$qtyz = mysql_query($ertz);
$tyui = mysql_num_rows($qtyz);
$data = array(
"post" => $fgh,
"likes" => $tyui
);
echo json_encode($data);
} else {
echo "0";
}
?>
Now comes the jquery part :-
<script>
$(document).ready(function(){
setInterval(function(){
var def = "one";
$.post("check_num.php", {'default': def }, function(response){
if(response != 0){
document.getElementById("total_array_count").innerHTML = response;
//document.getElementById("total_like_count").innerHTML = response.likes;
//document.getElementById("total_post_count").innerHTML = response.post;
------------------OR THIS Method-----------------
var my_array = response;
//var post_number = my_array["post"];
document.getElementById("total_array_count").innerHTML = my_array;
//document.getElementById("total_post_count").innerHTML = '<b>'+post_number+'</b>';
}
else {
document.getElementById("total_array_count").innerHTML='Error occured !';
}
});
},2500);
});
</script>
Now received output is {"post":10,"likes":1} , its an array . But when i access array values response.post or my_array["post"] the value returned is undefined.
I had gone through this :- http://www.w3schools.com/js/tryit.asp?filename=tryjs_array_object
And kind of this too:- jQuery .val() returns undefined for radio button
Followed it but no success !
Please correct my mistakes .
Run JSON.parse() on your result before trying to access the values. The result comes as a raw string and you have to convert it to an object first.
result = JSON.parse(result);
Alternatively, since you're already using jQuery, you can use jQuery's alias for the function.
result = $.parseJSON(result);
They are essentially the same thing.
i am trying to get the data which is in array, from an SQL query to the ajax success data. Here is the code i tried,
function adminchecksub(value1){
//alert('hi');
var value1=$('#adminsid').val();
//alert(value1);
if(value1==''){
alert('Please enter a Sub id');
}
else{
//alert(value1);
$.ajax({
type: 'POST',
url: root_url + '/services/services.php?method=adminsubcheck',
data: {value1:value1},
async: true,
success: function (data) {
alert(data);
if (data == 1) {
alert('inside');
//window.location.assign(rdurl+"?sid="+sid);
return true;
} else {
//alert('does not exist!');
//alert('outside');
return false;
}
}
});
}
now in the php method which is requested from the above ajax call, i have to get the data return by this function which is returning an array
function adminsubcheck($sid){
$subid=$sid['value1'];
$row = array();
//echo $subid;
$query = "SELECT Sub_id,Status,Sub_type FROM Sub WHERE Sub_id=$subid";
//echo $query;
//echo $subid;
$queryresult = mysql_query($query);
$count = mysql_num_rows($queryresult);
//echo $count;
while ($r = mysql_fetch_assoc($queryresult)) {
$row[] = $r;
}
return $row;
}
here $row is returning an array as data to the ajax function, where i need to get all the items seperately. Some one help me out to get the values into the ajax call. Thanks in advance..
In your PHP file, you can return your array as a json object in the following way (notice how the PHP file echos the result to pass it back to javascript)
...
$json = json_encode($row);
echo $json
Now add the following to your javascrip ajax
$.ajax({
...
// Whatever code you currently have
...
}).done(function ( json ) {
var data = JSON.parse(json);
//Continue with javascript
});
You can handle the java script variable 'data' as an associative array like it was in PHP
also, look how you populate the php variable $row and adjust the following way:
$cnt = 0;
while ($r = mysql_fetch_assoc($queryresult)) {
$row[$cnt] = $r;
$cnt++;
}
$json = json_encode($row);
echo $json;
in javascript you can access your rows the following way in teh data variable:
var value = data[0]['field_name'];
in the above statement, 0 will correspond to the value of $cnt (i.e. mysql returned row number)
return $row;
replace like this
echo json_encode($row);
and add dataType='json' in ajax like this
dataType: 'json',
If you want get the value in ajax call i think it shoul be :
while ($r = mysql_fetch_assoc($queryresult)) {
$row[] = $r;
}
echo json_encode(array('data'=>$row));
exit;
i am a noob to jquery and i want to know how to make use of if else for the following:
on the server side there is a if for number of rows is equal to 0 and else some JSON part.
$age= mysql_query("SELECT title FROM parent WHERE id ='$name'");
$age_num_rows = mysql_num_rows($age);
if ($age_num_rows==0)
{
echo "true";
}
else
{
$sql ="SELECT * FROM parentid WHERE id = '$name'"; //$name is value from html
$result = mysql_query($sql);
while($row = mysql_fetch_array($result))
{
$abc_output = array('title' => $row['title'],'age' => $row['age']);
}
echo json_encode($abc_output);
}
Now coming to Jquery part :
If the above PHP code go to if part then i want to display an alert box or if it goes to else part it needs to insert some values into the forms.
Here is something i tried but it did not work.
$(document).ready(function(){
$("#button1").click(function(){
$.getJSON('script_1.php',function(data){
if (data=='true') {
alert ('hello')
}
else {
$.post('script_1.php',
{ id: $('input[name="id"]', '#myForm').val() },
function(json) {
$("input[name='title']").val(json.title);
$("input[name='age']").val(json.age);
},
"json");
}
});
});
Edited:
$(document).ready(function(){
$("#button1").click(function(){
$.post(
'script.php',
{ id: $('input[name="id"]', '#myForm').val() },
function(json) {
var data = JSON.parse(json);
if (data.length === 0){
alert('no data');
}
else{
$("input[name='title']").val(json.title);
$("input[name='age']").val(json.age);
}},
"json"
);
});
});
PHP side
$name = mysql_real_escape_string($_POST['id']);
$sql ="SELECT * FROM parentid WHERE id = '$name'";
$result = mysql_query($sql);
$row = mysql_fetch_array($result);
if ($row) {
$row= array('title' => $row['title'],'age' => $row['age']);
echo json_encode($row);
} else {
echo json_encode(array());
}
You need to parse the JSON before you can use it like that. Modern browsers will have built in support for JSON.parse(yourJSON), but to account for those that don't, you should use Douglas Crockford's JavaScript JSON library. Including it will provide JSON.parse() if the browser doesn't have it already.
For the if-else stuff you're doing in the PHP, the common practice is to echo out an empty JSON object or array, so you don't have to test for things like no rows on the server side. You could do something as simple as this, later accounting for your database column names:
$result = mysql_query($sql);
$row = mysql_fetch_assoc($result);
if ($row) {
echo json_encode($row);
} else {
echo json_encode(array());
}
Back in the JavaScript, you could then do something like this:
var data = JSON.parse(json);
if (data.length === 0) {
alert('no data');
} else {
$("input[name='title']").val(data.title);
$("input[name='age']").val(data.age);
}
jeroen is right though, you only need to use one AJAX call.
There seem to be a few problems:
You are treating the data returned from getJSON as if it is plain
text
The php that you are calling from javascript does not always
return json
You are doing 2 ajax requests; getJSON and post where you only need one: The first call to getJSON without any data will never reach the else condition
By the way, where does $name come from in your php script? For your second ajax call to work, it needs to be something like mysql_real_escape_string($_POST['id']) or (int) $_POST['id'] if it is an integer.
Edit: I think it would be easiest to get rid of the .post and just use the first ajax call. So you will need to change:
$.getJSON('script_1.php',function(data){
to something like:
$.getJSON('script_1.php?id=' + $('input[name="id"]').val(), function(data) {
and in your php you need to use something like:
$name = mysql_real_escape_string($_GET['id']);
I create a huge JSON-Object and save it in my database. But when I load the "string" and echo it in PHP, I can't access the JSON Object in JQuery. Do I have to consider something if I want to save my JSON Object in a MySQL Database (when I just create the Array and then echo it with "echo json_encode($arr);" it works fine, but I need to save the Object for caching).
{"247":{"0":"This is a
question","1":"","2":"247","3":"0","answers":[["Answer1","960","1"],["Answer
2","962","0"],["Answer
3","961","0"],["Answer
4","963","0"]]},{"248":{"0":"This is a
question","1":"","2":"247","3":"0","answers":[["Answer1","960","1"],["Answer
2","962","0"],["Answer
3","961","0"],["Answer
4","963","0"]]}}
just an excerpt
If I just echo this JSON-Object, everything works fine, but if I load the same string from the database and echo it, it doesn't work.
Update 1: forget to tell that I'm using a TEXT-Field with UTF8_general_ci collation
Update 2: Maybe a little bit more code:
function start() {
$(".start").click(function () {
$.post("load_script.php", { }, function(data){
alert(data[247][0]);
}, "json");
return false;
});
}
this loads the script and should alert "This is a question"
<?php
require_once('connect.php');
$ergebnis = mysql_query("SELECT text FROM cache_table ORDER BY RAND() LIMIT 1");
while($row = mysql_fetch_object($ergebnis)) {
$output = $row->text;
}
echo $output;
?>
this is the script, where I load the database entry with the JSON-Object.
Update 3:
I think I solved the problem. Some break sneaked into my JSON-Object so I do this, before the output:
$output = str_replace("\n", "", $output);
$output = str_replace("\r", "", $output);
$output = str_replace("\r\n", "", $output);
I'd suggest looking at what your javascript is seeing. Instead of asking jQuery to interpret the json for you, have a look at the raw data:
function start() {
$(".start").click(function () {
$.post("load_script.php", { }, function(data){
alert(data);
}, "text");
return false;
});
}
For example, if part of the string gets oddly encoded because of the UTF-8, this might cause it to appear.
Once you've done that, if you still can't spot the problem, try this code:
var data1, data2;
function start() {
$(".start").click(function () {
$.post("load_script.php", {src: "db" }, function(data){
data1 = data;
}, "text");
$.post("load_script.php", {src: "echo" }, function(data){
data2 = data;
}, "text");
if (data1 == data2) {
alert("data1 == data2");
}
else {
var len = data1.length < data2.length ? data1.length : data2.length;
for(i=0; i<len; ++i) {
if (data1.charAt(i) != data2.charAt(i)) {
alert("data1 first differs from data2 at character index " + i);
break;
}
}
}
return false;
});
}
And then change the PHP code to either return the data from the database or simply echo it, depending on the post parameters:
<?php
if ($_POST['src'] == 'db')) {
require_once('connect.php');
$ergebnis = mysql_query("SELECT text FROM cache_table ORDER BY RAND() LIMIT 1");
while($row = mysql_fetch_object($ergebnis)) {
$output = $row->text;
}
}
else {
$output = '{"247":{"0":"This is a question","1":"","2":"247","3":"0","answers":[["Answer1","960","1"],["Answer 2","962","0"],["Answer 3","961","0"],["Answer 4","963","0"]]},{"248":{"0":"This is a question","1":"","2":"247","3":"0","answers":[["Answer1","960","1"],["Answer 2","962","0"],["Answer 3","961","0"],["Answer 4","963","0"]]}}';
}
echo $output;
?>
Hope that helps!
I got this to work in a slightly different manner. I've tried to illustrate how this was done.
In Plain English:
use urldecode()
In Commented Code Fragments
$json = $this->getContent($url); // CURL function to get JSON from service
$result = json_decode($json, true); // $result is now an associative array
...
$insert = "INSERT INTO mytable (url, data) ";
$insert .= "VALUES('" . $url . "', '" . urlencode(json_encode($result)) . "') ";
$insert .= "ON DUPLICATE KEY UPDATE url=url";
...
/*
** Figure out when you want to check cache, and then it goes something like this
*/
$sqlSelect = "SELECT * FROM mytable WHERE url='" . $url . "' LIMIT 0,1";
$result = mysql_query($sqlSelect) or die(mysql_error());
$num = mysql_numrows($result);
if ($num>0) {
$row = mysql_fetch_assoc($result);
$cache = json_decode(urldecode($row['data']), true);
}
Hope this is helpful
Maybe you use varchar field and your string just doesn't fit in 255 chars?