Ajax Implementation in Codeigniter
Ajax means Asynchronous Javascript and XML, it is used to partially update the content of a web page excluding complete web form.
Ajax improves the performance of web application and provide dynamic programming approach without reloading and submit the data.
for example, if we create a registration form and we want to check that email already exists when user switches to next text field then we can create ajax code to check the email id.
when we select country then the state list and when we select the state then the city list will be populated by AJAX.
when we search from Facebook or Google search box then data will be populated when we press any key that will be managed by Ajax.
Role of JavaScript or Jquery:-
It is used to handle the event in Ajax Process, which means if we select a dropdown list and display data into another dropdown list will be managed by AJAX.
Role of XML:-
XML means Extensible markup language which is used to transfer data from client machine(Browser) to server machine (Apache Server).
XMLHttpRequest:- this class is used to send data from browser to web server.
XMLHttpResponse:- It is used to get web server response using XML form.
AJAX EXAMPLE IN CI?
.....................................................................................................
Create Controller:-
<?php
class AjaxExample extends CI_Controller
{
function __construct()
{
parent::__construct();
$this->load->model('stumodel');
}
function index()
{
$this->load->view('ajaxview');
}
function searchdata($id)
{
$r = $this->stumodel->ajaxsearch($id);
if(count($r)>0)
$data['res']=$this->stumodel->ajaxsearch($id);
else
$data['res']="no record found";
$this->load->view('searchview',$data);
}
}
?>
..................................
View File:-
ajaxview.php
<!DOCTYPE html>
<html>
<head>
<title></title>
<script type="text/javascript">
function showdata(a)
{
if(a!='')
{
xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange=function()
{
document.getElementById("res").innerHTML=xmlhttp.responseText;
}
xmlhttp.open("POST","<?php echo site_url(); ?>/ajaxexample/searchdata/"+a,true);
xmlhttp.send();
}
}
</script>
</head>
<body>
<center>
<h1>Search Content</h1>
<input type="text" name="txt" onkeyup="showdata(this.value)" />
<div id="res"></div>
</center>
</body>
</html>
...........................................................
searchview.php
........................................................................
<!DOCTYPE html>
<html>
<head>
<title></title>
</head>
<body>
<?php
//print_r($res);
if(is_array($res))
{
foreach ($res as $x) {
foreach ($x as $y)
{
echo $y," ";
}
echo "<hr>";
}
}
else
echo $res;
?>
</body>
</html>
.............................................................................................................
Model:-
<?php
class Stumodel extends CI_Model
{
function __construct()
{
parent::__construct();
$this->load->database();
}
function ajaxsearch($id)
{
$res = $this->db->select('*')->from('student')->where("name LIKE '$id%'")->get()->result_array();
return $res;
}
}
?>
Ajax improves the performance of web application and provide dynamic programming approach without reloading and submit the data.
for example, if we create a registration form and we want to check that email already exists when user switches to next text field then we can create ajax code to check the email id.
when we select country then the state list and when we select the state then the city list will be populated by AJAX.
when we search from Facebook or Google search box then data will be populated when we press any key that will be managed by Ajax.
Role of JavaScript or Jquery:-
It is used to handle the event in Ajax Process, which means if we select a dropdown list and display data into another dropdown list will be managed by AJAX.
Role of XML:-
XML means Extensible markup language which is used to transfer data from client machine(Browser) to server machine (Apache Server).
XMLHttpRequest:- this class is used to send data from browser to web server.
XMLHttpResponse:- It is used to get web server response using XML form.
AJAX EXAMPLE IN CI?
.....................................................................................................
Create Controller:-
<?php
class AjaxExample extends CI_Controller
{
function __construct()
{
parent::__construct();
$this->load->model('stumodel');
}
function index()
{
$this->load->view('ajaxview');
}
function searchdata($id)
{
$r = $this->stumodel->ajaxsearch($id);
if(count($r)>0)
$data['res']=$this->stumodel->ajaxsearch($id);
else
$data['res']="no record found";
$this->load->view('searchview',$data);
}
}
?>
..................................
View File:-
ajaxview.php
<!DOCTYPE html>
<html>
<head>
<title></title>
<script type="text/javascript">
function showdata(a)
{
if(a!='')
{
xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange=function()
{
document.getElementById("res").innerHTML=xmlhttp.responseText;
}
xmlhttp.open("POST","<?php echo site_url(); ?>/ajaxexample/searchdata/"+a,true);
xmlhttp.send();
}
}
</script>
</head>
<body>
<center>
<h1>Search Content</h1>
<input type="text" name="txt" onkeyup="showdata(this.value)" />
<div id="res"></div>
</center>
</body>
</html>
...........................................................
searchview.php
........................................................................
<!DOCTYPE html>
<html>
<head>
<title></title>
</head>
<body>
<?php
//print_r($res);
if(is_array($res))
{
foreach ($res as $x) {
foreach ($x as $y)
{
echo $y," ";
}
echo "<hr>";
}
}
else
echo $res;
?>
</body>
</html>
.............................................................................................................
Model:-
<?php
class Stumodel extends CI_Model
{
function __construct()
{
parent::__construct();
$this->load->database();
}
function ajaxsearch($id)
{
$res = $this->db->select('*')->from('student')->where("name LIKE '$id%'")->get()->result_array();
return $res;
}
}
?>
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