Dynamic AJAX DD from Javascript nested array - php

Basically I have the most popular code in the world for a dynamic dependant dropdown using PHP & MySQL, but I'm trying to populate the select option text and option value from an array, let's say the id as the option value, and the name as the option text; I found a thread that exactly depicts what I am trying to do, but it is not working for me (the dyanmic dropdown works like a charm).Here's the link:
http://forums.phpfreaks.com/index.php?topic=287884.0
And here's my code;
`for (i=0;i<myarray.length;i++)
{
var optn = document.createElement("OPTION");
optn.text = myarray[i][0];
optn.value = myarray[i][1];
document.testform.id_proveedor.options.add(optn);
}`
And the part of the code from the dd.php
`while($nt=mysql_fetch_array($q)){
$str=$str.'new Array("'.$nt[id_proveedor].'","'.$nt[nombre].'"),';
}
$str=substr($str,0,(strLen($str)-1)); // Removing the last char , from the string
echo "new Array($str)";`
Any ideas on why the code is not working?
Thanks in advance!!

I think that this script uses "evaluate" function of javascript and I don't think it is a good think.
IMO the best practice would be such a code in php, using JSON
$result = array();
while($nt=mysql_fetch_array($q)){
$result[]=$nt;
}
echo json_encode($result);
And in your AJAX code you just have to use var myarray=JSON.parse(response);to have your array to traverse.

Related

Iterate through php array in jquery

So I have a php array that I am JSON encoding and handing to some JQuery. Basically I am using the information from the array to dynamically change the content of one drop down based on the value of another drop down. I am running into some problems with the JQuery though as JQuery is pretty new to me.
First off my PHP:
<?php
$sql = mysql_query("SELECT * FROM menu") or die(mysql_error());
$menuItems = array();
$x = 0;
while($row = mysql_fetch_object($sql))
{
$menuItems[$x]['ID'] = $row->ID;
$menuItems[$x]['parent'] = $row->parent;
$menuItems[$x]['name'] = $row->Name;
$menuItems[$x]['header'] = $row->header;
$menuItems[$x]['Sort'] = $row->sort;
$x++;
}
?>
This code returns an array of ~30 menu items.
Then my JQuery:
<script>
var menuItems = <?php echo json_encode($menuItems); ?>;
$('#dropdown1').change(function (){
if($('#dropdown1').val() == 0){
$('dropdown2').children().remove().end()
for(var x = 0; x < menuItems.length; x++){
if(menuItems[x]['header'] == 1){
$('#dropdown2').options[menuItems[x]['sort']] = new Option(menuItems[x]['name'], menuItems[x]['sort']);
}
}
}
});
</script>
What I want this to do is when dropdown1 is changed, dropdown2's options are removed and then repopulated with specific things from the array.
Currently this code does delete the options for dropdown2 when dropdown1 is changed but re-population just isn't working. From what I can tell in testing, the for loop to iterate through the array is only entered once, despite their being about 30 items in it and I assume that is were my main problem is.
What am I doing wrong here?
change it to
for(var x = 0; x < menuItems.length; x++){
if(menuItems[x]['header'] == 1){
var option = $('<option />', {
text : menuItems[x]['name'],
value: menuItems[x]['sort']
});
$('#dropdown2 option[value="'+[menuItems[x]['sort']]+'"]').replaceWith(option);
}
}
$('#dropdown2').options[] is not valid, as jQuery doesn't have those methods, that's for plain JS DOM nodes.
So from the comments there seemed to be some confusion on what I meant, and I apologize. It was one of the instances where the explanation made sense to me, but I just must not have conveyed everything well enough.
To clear up a little bit of the confusion. The array that was passed from the PHP code to the javascript contained everything I could ever need for the second drop-down.
As many pointed out the .options[] was the culprit for why the code wasn't executing. This was simply from another example I had found, and with my limited knowledge I assumed it was correct, and it wasn't.
I instead used the the .append() function and things seem to be working normally now.

Save JavaScript array to server using PHP

I have recently started coding with javascript/php using the Cloud9 IDE.
I know this may be a duplicate of some questions on here, but I have yet to find a solution that works for me.
I have an array of custom javascript objects that I would like to save to a file on the server (later to be retrieved to repopulate data on the page):
<script>
var questionList = [];
function saveToFile() {
var x =JSON.stringify(questionList);
$.post("saveQuestion.php", {data : x}, function(){alert("File saved successfully")});
}
</script>
//in the body of the html
<button id="saveToFileButton" type="button" onclick='saveToFile()'>Save to file</button>
The php file 'saveQuestion.php' is in the same directory, and is as follows:
<?php
$data = $_POST['data'];
file_put_contents("savetest.txt", $data);
?>
However, despite my best efforts, 'savetest.txt' remains empty.
I know that 'x' is being assigned the correct value as I can print it out to a html element.
Edit: The php script has permission to write to the file, but as far as I can tell it is never called. What would be a possible cause/solution to this?
Can someone offer a simple explanation that highlights what I am doing wrong and possible ways to fix it?
Thanks!
Maybe you should assign the questionsList array some values:
<script>
// Check if your assigning a value to this array
var questionList = ['value 1', 'value 2', 'etc..'];
function saveToFile() {
var x =JSON.stringify(questionList);
$.post("saveQuestion.php", {data : x}, function(){alert("File saved successfully")});
}
</script>

PHP jQuery dynamically populated SELECT

Have been looking around for a solution to this and have found some help on stack overflow but in most cases the examples I have found are not using arrays formed from a database query. Here is some code for what I am trying to achieve...
$stores = mysql_query("SELECT * FROM Stores");
$staff = mysql_query("SELECT * FROM Staff");
I would like to create two elements, one for stores and another for staff but I want to filter the staff based on the store client side. So if the user selects "Sydney" from the first dropdown, they are presented with only staff that work at the Sydney store in the second dropdown. Then if the user chooses "London" from the first dropdown, the Sydney staff are replaced by the London staff and so on.
My server side scripting is done with PHP and I am able to create the two dropdowns with PHP. But I am stuck on the jQuery to remove the I don't want from the second dropdown.
I know this is possible, because I see it used all the time. I have seen lots of examples of how to manage this but none of the examples use data from the PHP array to insert the .
You need ajax.
When the user selects something in a dropdown, this fires an event that you can process. Inside of this process you take the value of the selection like jQuery('#id_dropdown').val(), and send this via ajax (I like using POST since you dont run into GET request size limits).
You process this on the server side with php, accessing to the database with the value selected and sent via ajax. When you have the right results for the second dropdown you can output it via echo.
Finally, when the response is returned to jQuery, you can insert all the options in the new dropdown.
JAVASCRIPT PART:
Bind event to the first dropdown
Get value of the option selected in the dropdown
Make ajax request
Here is some example code:
var parameters='value_selected='+value_dropdown;
jQuery.Post({
url: '/destiny_when_I_process',
data: parameters,
success: func_callback
});
//here you can imagine a pause, because PHP is processing the data you send by post
//....
//....
//this part is executed when php send the information
function func_callback(response_from_php){
jQuery('#second_dropdown').html(response_from_php);
}
PHP PART:
get value from POST
access database using this value
echo (send response). You send a chain of text (in HTML), really this is not very professional, but is OK for demonstration purposes. Professionals send JSON, since JSON is lighter-weight.
JAVASCRIPT PART (SECOND PART)
in the callback function, you receive the response data via the first parameter
Insert new data in the second dropdown (since the data is already HTML, you do not need to process it)
for the secondary drop down, yes, you'll need some ajax.
You can create a script that go fetch the result coresponding to the store and send back the option listm witch is inserted in the ooption.
Using jquery and php you'll need a few thing.
A php file to get the result and return the options. (let say getStaff.php)
<?php
//get the store id by post is it is set
if (isset($_POST['store->id']) $store_id = mysqli_real_escape_string($_POST['store_id']);
//get the data !! notice the WHERE caluse
$r = mysql_query("SELECT * FROM Staff" *WHERE store=''$store->is*);
//split the data in the array
$staffs=array();
while ($assoc = mysql_fetch_assoc($r)) {
//Varialbe = $assoc['colum_name'];
$staff->id=$assoc['id'];
$staff->name=$assoc['name'];
//and so on for each colum in your table.
array_push($staffs, $assoc);
}
//echo the result as option
foreach ($staffs as $staff) echo "<option value='$staff->id'>$staff->name</option>";
?>
In you first select, add
onchange="$.post('getStaff.php', {store_id:$(this).val()}, function (data){ $('#staff_select').html(data);});"
and add an id to your second select (staff_select) in this ecample.
As an explanation: When the 1st dropdown change, it send a request to getStaff.php with the store_id as a POST argument. The php sript get the syaff according to the store Id and bring back a list of option tags for your secondary select. Than jquery add the 'data' to your secondary select and VOilĂ !
Hope tih sis clear cause it's a bunch of little thing together that will make it work. Sorry if it's seems sloppy as an answer but it's really simple once you know it.
Spent the afternoon learning how to do this and it's working quite well. Posted the new code here for others....
Thanks to http://forum.codecall.net/topic/59341-php-sql-jquery-and-ajax-populate-select-boxes/ for the tutorial.
And thanks to everyone here.
PHP to build for the first :
function agency_select() {
include('../include/dbase.php');
$agencies = $pdo->query("SELECT * FROM agency WHERE Status='active' ORDER BY AgencyName");
$opt = '';
while ($age_array = $agencies->fetch(PDO::FETCH_ASSOC)) {
$opt .= '<option value="'.$age_array['AgencyId'].'">'.$age_array['AgencyId'].' - '.$age_array['AgencyName'].' - '.$age_array['AgencySuburb'].'</option>'."\n\t\t\t\t\t\t\t";
}
return $opt;
}
HTML for the two elements:
<label for="AgencyId">Client/Agency:</label>
<select class="uniform" id="AgencyId" name="AgencyId" style="width: 400px; overflow-x: hidden">
<?php echo agency_select(); ?>
</select>
<label for="Contact">Contact: </label>
<select class="uniform" id="Contact" name="Contact" style="width: 300px; overflow-x: hidden">
<option value="">----Select Client/Agency----</option>
</select>
AJAX file:
if(isset($_POST['AgencyId'])) {
include('../include/dbase.php');
$option = '<option value="">----Select Contact----</option>';
$query = $pdo->prepare("SELECT * FROM client WHERE AgencyId= ? AND Status='active' ORDER BY FirstName");
$result = $query->execute(array($_POST['AgencyId'])));
while ($row = $result->fetch(PDO::FETCH_ASSOC)) {
$option .= '<option value="'.$row['id'].'">'.$row['FirstName'].' '.$row['LastName'].'</option>';
}
echo $option;
}
jQuery:
$(document).ready(function () {
update_contacts();
});
function update_contacts() {
$('#AgencyId').change(function() {
$('#Contact').fadeOut();
$('#loader').show();
$.post('../ajax/ajax_contact_select.php', {
AgencyId: $('#AgencyId').val()
}, function (response) {
setTimeout("finishajax('Contact', '"+escape(response)+"')", 400);
});
return false;
});
}
function finishajax(id,response) {
$('#loader').hide();
$('#'+id).html(unescape(response));
$('#'+id).fadeIn();
}
i'll try to help you as much as i can a explain it.
mysql_query, you sould use mysqli btw, mtsql being decrecated, return a result set.
This means you will have all the records from your query. You need to brak down your result into before you can work with it. This is done by using methids like mysql_fetch_assoc, mysql_fetch_row, etc. There something like fetch to array to but i don't master it so i will use fetch assoc, for this reply.
So once you have yoru result set, $stores & $staff in your case, you then call a while loop on your results to get th data as in:
while ($assoc = mysql_fetch_assoc($r)) {
//Varialbe = $assoc['colum_name'];
$stores->id=$assoc['id'];
$stores->name=$assoc['name'];
//and so on for each colum in your table.
array_push($stores, $assoc);
}
Then you can export it as you want.
in you case would be something like
foreach ($stores as $store) echo "<option value='$store->id'>$store->name</option>";
I storngly suggest you take alook at http://php.net/manual/en/function.mysql-fetch-array.php witch will do the same a fetch_assoc bu with an array with the columname as key.

Including JavaScript in PHP function Error

I had a weird problem here. Please check the code below. I do not understand how this code below is created by somehow part of it is working, considering mixture of php variables and javascript variables.
First, let us see what the alert() outputs (take note that $lat and $lng is different from the array $vlat):
In Line 8 of the code below, alert(eventlocation) properly displays the coordinates of the GoogleMap latlng (so the implementation is correct)
In Line 13, alert(s) was able to display incrementing values (i.e. 0,1,2,3,4,..) based on the for loop in the previous line so it is also correct.
In Line 14, alert($vlat[0]) was able to display the latitude of the first element of that array (declared before this set of codes) so it is also correct
In Line 15, alert($vlat[1]) was able to display the latitude of the second element of that array so it is also correct
But in Line 16, alert($vlat[s]) displayed undefined.
Can anyone explain that? Thanks
echo "<script src= 'http://maps.google.com/maps?file=api&v=2&key=ABQIAAAA2jrOUq9ti9oUIF0sJ8it1RTNr3PHi_gURF0qglVLyOcNVSrAsRRu2C3WQApcfD0eh9NLdzf9My0b9w' type='text/javascript'> </script>
<script language='javascript' type='text/javascript'>
function getabc(){
var eventlocation;
var volunteerlocation;
var s;
eventlocation = new GLatLng($lat, $lng);
//alert(eventlocation);
var volunteerDist = new Array();
s = $ctr;
var tvid = new Array();
for(s=0;s<$numrows;s++){
//alert(s);
//alert($vlat[0]);
//alert($vlat[1]);
//alert($vlat[s]);
}
}
a = getabc(); < /script>";
alert($vlat[0]);
alert($vlat[1]);
alert($vlat[s]);
$vlat[0], $vlat[1] and $vlat[s] are parsed on the server before they is sent to the client. The first two can be resolved, but PHP does not know what s is, since s is only defined once the client side is reached.
Edit from chat discussion
$json = json_encode($vlat);
echo "<script language='javascript' type='text/javascript'>
function test(){
var obj = JSON.parse('$json');
alert(obj);
}
< /script>";
The variable s that you are using to index the PHP array vlat is a variable that you declared in JavaScript. You cannot use it to index a PHP array.
What your code tries to do is to have PHP access a JavaScript variable, which it cannot. You can have PHP echo JavaScript, yes, but it doesn't work both ways.

Use php to populate javascript array

All,
I have the following bit of code:
function addPoints() {
newpoints[0] = new Array(41.45998, 87.59643, icon0, 'Place', 'Content to open');
for(var i = 0; i < newpoints.length; i++) {
var point = new GPoint(newpoints[i][1],newpoints[i][0]);
var popuphtml = newpoints[i][4] ;
var marker = createMarker(point,newpoints[i][2],popuphtml);
map.addOverlay(marker);
}
}
There is other code around this to display the marker on my map. However this value is hardcoded. I have a PHP/mySQL database that has lat/long coordinates along with some other values. Say I have like three entries that I want to create markers for. How would I pass the addPoints function the lat/long that I got from my database so I can use it in this function correctly?
I updated my code to look like the following for the addPoints:
function addPoints(num, lat, long) {
newpoints[num] = new Array(lat, long, icon0, 'Place', 'Stuff name');
alert("The newpoints length is: "+newpoints.length);
for(var i = 1; i < newpoints.length; i++) {
var point = new GPoint(newpoints[i][1],newpoints[i][0]);
var popuphtml = newpoints[i][4] ;
var marker = createMarker(point,newpoints[i][2],popuphtml);
map.addOverlay(marker);
}
}
I call this function by doing this:
<script>
addPoints('<?php echo json_encode($num_coordinates); ?>','<?php echo json_encode($lat_coordinates); ?>', '<?php echo json_encode($long_coordinates); ?>');
</script>
It doesn't work though. When I try not to pass it to javascript and just output the lat coordinates for example. I get the following output:
{"1":"40.59479899","2":"41.4599860"}
Which are the correct coordinates in my array. No markers get created though. Any ideas on what to do next or what I'm doing wrong?
An easy and clean way to pass an array from PHP to JavaScript is to simply echo the json_encode version of the array.
$array = array(1,2,3,4,5,6);
echo 'var values = '.json_encode($array).';';
PHP executes on the server before getting sent to the the client. Therefor, if you can do things like this:
newpoints[0] = new Array(<?php echo $lattitude;?>, <?php echo $longitude;?>, icon0, 'Place', 'Content to open');
Where $lattitude and $longitude are values that you pulled out of you database with PHP.
When this page is requested by the client, your php code executes, real values get plugged in where those php tags are making it look like the example you provided, and then it gets sent to the client.
If you want to change these values using JS on the client, or fetch new ones from the server, let me know and I'll add an example of that.
EDIT:
Okay, in light of your comments, it sounds like you've got a few options. Here's one:
When the user selects a category (restaurants, bars, etc) you pass that category as a url parameter and reload either the whole page, or just the map part of it (depends on your set up but might be worth investigating). Your link would look something like this:
http://www.your-domain-here.com/maps.php?category=bars
Maps.php is ready to catch the category using the $_GET array:
$category = $_GET['category']; //'bars'
Your php then grabs the appropriate location data from the database (I'll leave that part to you) and sticks it in a variable that your JS-controlled map will be able to use:
//JS in maps.php - you could add this var to the window object
// if you have separated js files...
var locationCoords = <?php echo json_encode($arrayOfCoordinatesFromDB);?>;
When you page loads on the client machine, it now has an array of coordinates to use for the map ready to go in the locationCoords variable.
Then, depending on which coordinates you need to display on the map, you pass them as arguments to your addPoints() using standard Javascript (nothing tricky here).
That's how I'd do it. Hope that helps!
It is as simple as echoing the php values.
new Array(<?php echo $php_lat;?>, <?php echo $php_long;?>, icon0 etc...
I made a dynamic banner with this javascript array initialization. It works fine when the javascript is embedded in php.
<?php
// This is our php array with URLs obtained from the server
$urlsPHP = ["img/img01.jpg","img/img02.jpg","img/img03.jpg"];
return = "
//...Some HTML...
<script type='text/javascript'>
// Now we use this inside the javascript
var urlsJavaScript = ".stripslashes(json_encode($urlsPHP)).";
//...Some javascript style to animate the banner...
</script>
";
// if we print this:
echo stripslashes(json_encode($urlsPHP));
// We obtain:
// ["img/banner/bak01.jpg","img/banner/bak02.jpg","img/banner/bak03.jpg"]
// This is a good syntax to initialize our javascript array
// if we print this:
echo json_encode($urlsPHP);
// We obtain:
// ["img\/banner\/bak01.jpg","img\/banner\/bak02.jpg","img\/banner\/bak03.jpg"]
// This is not a good syntax to initialize our javascript URLs array
?>

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