Getting a record row in php using javascript - php

Question

Coming from Adobe Flex I am used to having data available in an ArrayCollection and when I want to display the selected item's data I can use something like sourcedata.getItemAt(x) which gives me all the returned data from that index.
Now working in php and javascript I am looking for when a user clicks a row of data (in a table with onClick on the row, to get able to look in my data variable $results, and then populate a text input with the values from that row. My problem is I have no idea how to use javascript to look into the variable that contains all my data and just pull out one row based on either an index or a matching variable (primary key for instance).
Anyone know how to do this. Prefer not firing off a 'read' query to have to bang against the mySQL server again when I can deliver the data in the original pull.
Thanks!

Answer 1

I'd make a large AJAX/JSON request and modify the given data by JavaScript.
The code below is an example of an actual request. The JS is using jQuery, for easier management of JSON results. The container object may be extended with some methods for entering the result object into the table and so forth.
PHP:
$result = array();
$r = mysql_query("SELECT * FROM table WHERE quantifier = 'this_section'");
while($row = mysql_fetch_assoc($r))
$result[$row['id']] = $row;
echo json_encode($result);
JavaScript + jQuery:
container.result = {};
container.doStuff = function () {
// do something with the this.result
console.debug(this.result[0]);
}
// asynchronus request
$.ajax({
url: url,
dataType: 'json',
data: data,
success: function(result){
container.result = result;
}
});

Answer 2

This is a good question! AJAXy stuff is so simple in concept but when you're working with vanilla code there are so many holes that seem impossible to fill.
The first thing you need to do is identify each row in the table in your HTML. Here's a simple way to do it:
<tr class="tablerow" id="row-<?= $row->id ">
<td><input type="text" class="rowinput" /></td>
</tr>
I also gave the row a non-unique class of tablerow. Now to give them some actions! I'm using jQuery here, which will do all of the heavy lifting for us.
<script type="text/javascript">
$(function(){
$('.tablerow').click(function(){
var row_id = $(this).attr('id').replace('row-','');
$.getJSON('script.php', {id: row_id}, function(rs){
if (rs.id && rs.data) {
$('#row-' + rs.id).find('.rowinput').val(rs.data);
}
});
});
});
</script>
Then in script.php you'll want to do something like this:
$id = (int) $_GET['id'];
$rs = mysql_query("SELECT data FROM table WHERE id = '$id' LIMIT 1");
if ($rs && mysql_num_rows($rs)) {
print json_encode(mysql_fetch_array($rs, MYSQL_ASSOC));
}

Answer 3

Maybe you can give each row a radio button. You can use JavaScript to trigger an action on selections in the radio button group. Later, when everything is working, you can hide the actual radio button using CSS and make the entire row a label which means that a click on the row will effectively click the radio button. This way, it will also be accessible, since there is an action input element, you are just hiding it.

Answer 4

I'd simply store the DB field name in the td element (well... a slightly different field name as there's no reason to expose production DB field names to anyone to cares to view the page source) and then extract it with using the dataset properties.
Alternatively, you could just set a class attribute instead.
Your PHP would look something like:
<tr>
<td data-name="<?=echo "FavoriteColor"?>"></td>
</tr>
or
<tr>
<td class="<?=echo "FavoriteColor"?>"></td>
</tr>
The javascript would look a little like:
var Test;
if (!Test) {
Test = {
};
}
(function () {
Test.trClick = function (e) {
var tdCollection,
i,
field = 'FavoriteColor',
div = document.createElement('div');
tdCollection = this.getElementsByTagName('td');
div.innerText = function () {
var data;
for (i = 0; i < tdCollection.length; i += 1) {
if (tdCollection[i].dataset['name'] === field) { // or tdCollection[i].className.indexOf(field) > -1
data = tdCollection[i].innerText;
return data;
}
}
}();
document.body.appendChild(div);
};
Test.addClicker = function () {
var table = document.getElementById('myQueryRenderedAsTable'),
i;
for (i = 0; i < table.tBodies[0].children.length; i += 1) {
table.tBodies[0].children[i].onclick = Test.trClick;
}
};
Test.addClicker();
}());
Working fiddle with dataset: http://jsfiddle.net/R5eVa/1/
Working fiddle with class: http://jsfiddle.net/R5eVa/2/