How can I use a Javascript function parameter to choose an array element?

Hi, ‪‎Javascript‬ friends!
How can I use a function parameter to choose an array element?

Example:

function populateSelect(id_select, function_name, field) {
if ($('#'+id_select).size() == 1) {
$.post('php/db_functions.php', 'function='+function_name, function(data, textStatus) {
elements = data.items;
$.each(elements, function(index, elements) {
$('#'+id_select).append('<option value="' + elements.id + '">' + elements.field + '</option>'); // I would like to use in this row the field parameter
});
$('#'+id_select).trigger('change');
}, "json");
}
}

Open in new window

LVL 1
ltpittAsked:
Who is Participating?
 
Tom BeckCommented:
You can pass whatever data you need through the post using name:value pairs.

$.post('php/db_functions.php', {  function_name : field }, function(data, textStatus) {

    ...

)};

Then test for the names in the $_POST array on the php side. Let's say the function name passed is 'getData'. It's value will be the field name you want to pass to the php function.

<?php

if (isset($_POST['getData'])) {
       //call the actual getData() function
        getData($_POST['getData']);
}

function getData(field) {
}

?>
0
 
Tom BeckCommented:
Change elements.field to:

field[index]
0
 
ltpittAuthor Commented:
I don't get it...

Can you please be more explicit with code example?
0
Ultimate Tool Kit for Technology Solution Provider

Broken down into practical pointers and step-by-step instructions, the IT Service Excellence Tool Kit delivers expert advice for technology solution providers. Get your free copy now.

 
Tom BeckCommented:
Maybe I misunderstood the question. You are passing the field parameter, an array according to your question, to the populateSelect() function. The comment in the $.each loop says you want to use the field parameter in the row. You had <option value="' + elements.id + '">' + elements.field + '</option>. You are using "field" as if it were a property of "elements". If field is an array then you must use an index to access the items inside. You have assigned the variable "index" to represent the index of the $.each loop. So field[index] will access the items in the field array. Caution: if elements.length is more than field.length, you are going to get an error.
function populateSelect(id_select, function_name, field) {
if ($('#'+id_select).size() == 1) {
$.post('php/db_functions.php', 'function='+function_name, function(data, textStatus) {
elements = data.items;
$.each(elements, function(index, elements) {
$('#'+id_select).append('<option value="' + elements.id + '">' +field[index] + '</option>'); // I would like to use in this row the field parameter
});
$('#'+id_select).trigger('change');
}, "json");
}
}

Open in new window

0
 
ltpittAuthor Commented:
I'm sorry but I see I was unclear...

All I wanto to do is populate 3 select in my html page.

Each select's array comes from a different table from the database.

From the sake of learning and writing better code I'd like to write a single populateSelect function instead of writing 3 specific function (one for each select to populate).

For this reason the "field" parameter would be the column name i'd need to get from the db...

I hope I was clearer this time: sorry for wasting your time :(
0
 
ltpittAuthor Commented:
oh so you'd pass right from the php just the right data I need.

So simple I feel stupid: thanks!
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.