This article is more than 1 year old
Xajax and PHP: JavaScript without the pain
Automatic for the people
Also specify in the tags of the input form that Xajax should generate any required JavaScript after an XML response has been sent back from the server.
<?php $xajax->printJavascript('./xajax'); ?>
A XMLHttpRequest
is initiated by a client application. In the example application, a XMLHttpRequest
is initiated by the onkeyup
event handler in input field catalogId
.
<tr><td>Catalog Id:</td><td><input type="text" size="20" id="catalogId" name="catalogId" autocomplete="off" onkeyup="xajax_validateCatalogId(xajax.getFormValues('validationForm'));"></td> <td><div id="validationMessage"></div></td> </tr>
The input field invokes the wrapper function xajax_validateCatalog
with an array of form field values as a parameter. The wrapper functions send a XMLHttpReques
to the server. The xajax
object receives the XMLHttpRequest
and invokes the corresponding PHP function validateCatalogId($formValues)
.
Process an Ajax request
Xajax provides the xajaxResponse
class to send a response to the client application. In the validateCatalogId
function, create a xajaxResponse
object.
$objResponse = new xajaxResponse();
The validateCatalogId
function validates a Catalog Id value added in the input form. From the $formValues
array retrieve the value of the catalogId
field.
$catalogId=trim($formValues['catalogId']);
Next, use the PHP Oracle extension to connect with the Oracle database and determine if a Catalog
table row is defined for the catalog id value input in the input form. If the result set is empty, a Catalog
table row for the catalog id value is not defined in the database table. Therefore, the Catalog Id field value added in the form is valid.
Next, we shall generate a response to be sent to the client application. A response contains one or more command messages. Some of the commonly used command messages are discussed in table below.
Command Message | Description |
---|---|
Assign | Sets the specified attribute of an element in input page with method addAssign(). |
Append | Appends data to the specified attribute of an element in the input page with method addAppend(). |
Prepend | Prepends data to the specified attribute of an element in the input page with method addPrepend(). |
Replace | Replaces data in the specified attribute of an element in the input page with method addReplace(). |
Script | Runs the specified JavaScript code with method addScript(). |
Alert | Displays an alert box with the specified message with method addAlert(). |