Mick Redman: Bootstrap formhandler calling class methods with JSON returned and processed

Wednesday, 10 June 2015

Bootstrap formhandler calling class methods with JSON returned and processed

This entry offers a number of techniques through 4 files.

index.php contains a message alert which will only be displayed when there is a message to put in it. The forms use an action which contains the name of a class and method which will be used to process the results. There is also a call to custom.js
custom.js handles the form submissions and delivers the data returned to the page. It passes the form action and field content to formhandler.php. It receives JSON which then is either passed to a message alert or a data table.
formhandler.php receives the call from custom.js. This contains the form action and field content. It takes the form action and uses them to create calls to classes and methods named in the form action. For example and action of myclass/mymethod would be used to create calls similar to those below. The inclusion of the $_POST array allows the form field content to be passed to the class. The data returned is then passed back to custom.js for processing.

$myclass = new myclass($_POST);
$myclass->mymethod;

myclassname.class.php contains the example class and methods. The class receives the $_POST array and processes its content. There are 3 methods which demonstrate how to return a string, an array and an object.

This approach is a quick way of utilising many classes. It does not require a .htaccess file to simplify form actions and is flexible in its handling of returned data through JSON.
Have fun.

index.php

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Form handler for many PHP classes using jQuery</title>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css">

<style>
body
{
margin-top:2em;
}
#message, #data-table
{
display:none;
}
</style>
</head>
<body>
<div class="row">
<div class="container">
<div class="col-md-12">
<div id="message" class="alert alert-success" role="alert"></div>


<form action="myclassname/myclassmethod_object" method="POST">
<div class="form-group">
<label for="name"></label>
<input type="text" name="name" class="form-control" />
</div>
<button type="submit" class="btn btn-default">Submit</button>
</form>
<table id="data-table" class="table table-striped">
<thead>
<tr>
<th>Name</th>
<th>Age</th>
</tr>
</thead>
<tbody>
</tbody>
</table>
</div>
</div>
</div>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script>
<script src="custom.js"></script>
</body>
</html>

custom.js

formhandler.php

<?php
if(isset($_GET['action']))
{
$arr = split('/', $_GET['action']);
$class = $arr[0];
$method = $arr[1];
require_once $class.'.class.php';
if(class_exists($class))
{
$evalStr = '$'.$class.' = new '.$class.'($_POST);';
eval($evalStr);
if(method_exists($class, $method))
{
$evalStr = '$returnValue = $'.$class.'->'.$method.'();';
eval($evalStr);
}
else
{
$returnValue = 'Method does not exist';
}
}
else
{
$returnValue = 'Class does not exist';
}
}
else
{
$returnValue = 'No action given';
}

if(is_object($returnValue) || is_array($returnValue))
{
echo json_encode($returnValue);
}
else
{
$returnArr = array('message'=>$returnValue);
echo json_encode($returnArr);
}
?>

myclassname.class.php

<?php
class myclassname
{
private $pa;
function __construct($postArray = array())
{
$this->pa = $postArray;
}

function myclassmethod_string()
{
return 'Your name is '.$this->pa['name'];
}

function myclassmethod_array()
{
$myArr = array('Peter'=>'35', 'Ben'=>'37', 'Joe'=>'43');
return $myArr;
}

function myclassmethod_object()
{
$myObj = (object) array('Peter'=>'35', 'Ben'=>'37', 'Joe'=>'43');
return $myObj;
}

function __destruct()
{

}
}
?>

Mick Redman