Answer: <?php $w3 = "mailto:info@w3answers.com"; preg_match('|.*@([^?]*)|', $w3, $w3output); echo $w3output[1]; ?> ....! There are a few inbuilt options you can use however, for example getimagesize() can return the mimetype, as does some of the new fileinfo functions. The mime type in getimagesize is stored in 'mime', and can be accessed as shown below. <?php $parts = getimagesize($filename); echo $parts['mime']; ?> or <?php $parts = getimagesize($filename); $allowedMimes = array('image/jpg', 'image/png', 'image/gif'); if(in_array(....! Ans: asort() arsort() ksort() krsort() uksort() sort() natsort() rsort() ....! The main difference between GET and POST is how the form data is passing. Both are used for passing form field values. All the values which is submitted by the GET method will be appended to the URL.Where as POST method send the data with out appending the URL(hidden) In GET Method we can bookmark the URLs where as in POST method its not possible In GET Method there is a limit for passing the data from one page to another(ie 256 characters according to w3c standards)But in POST we can send large amount of data function isbn10_to_13($isbnold){ if (strlen($isbnold) != 10){ // Make sure we have a 10 digit string to startreturn 'Invalid ISBN-10, must be 10 digits';} // prefix with 978 and drop old checksum (last digit)$isbn = '978'.substr($isbnold,0,9); for ($i = 0; $i <= 12; $i++){ // For each digit if new isbn$weight = ($i%2 == 0)? 1 : 3; // Alternate between 1's and 3's$check_sum_total = $check_sum_total + ($isbn{$i} * $weight); // multiply each digit by 1 or 3 and add to $checksumtotal} $....! a) // b) /* fgfg */ c) All of the above d) First one ANS: All of the above ....! Asynchronous JavaScript and XML, is a web development technique for creating interactive web applications. The intent is to make web pages feel more responsive by exchanging small amounts of data with the server behind the scenes, so that the entire web page does not have to be reloaded each time the user requests a change. This is meant to increase the web page's interactivity, speed, and usability. The Ajax technique uses a combination of: * XHTML (or HTML) and CSS, for marking up and styling information.....! Authentication is the process of determining whether someone or something is, in fact, who or what it is declared to be. In private and public computer networks (including the Internet), authentication is commonly done through the use of logon passwords. Knowledge of the password is assumed to guarantee that the user is authentic. Each user registers initially (or is registered by someone else), using an assigned or self-declared password. On each subsequent use, the user must know and use the previously declared password. The weakness in this syst....! PHP to ASP Let's first look at how you can pass data from PHP to ASP using WDDX. You create a WDDX packet by first serializing data into a WDDX packet and then presenting it. WDDX can convert most variable types that applications use, such as strings, integers, and arrays. After a variable has been converted to a WDDX variable type, it is ready for another application to pick up. PHP has WDDX support built in, so you don't need to modify your PHP.ini file to start using WDDX. A ....! When a user first encounters a page in your application that call ssession start(),a sessionis created for the user.PHP generates a random session identifier to identify the user,and then it sends a set-Cookieheader to the client.By default,the name of this cookie is PHPSESSID,but it is possible to change the cookiename in php.ini or by using the session name() function.On subsequent visits,the client identifies the user with the cookie,and this is how thea application maintains state. <?php $p = getcwd(); echo $p; ?> Ans: getcwd() Here I have stored my files under httdocs (using php5,i haven't checked under php4) so I get the output as C:\apache2triad\htdocs you may get your path information while runnings the above code. :)   The Session Manager session support allows multiple server instances to share a common pool of sessions, known as a session cluster Session clustering setting up methods : #1)First methods, is to have a NFS shared where session will be store. Setting this is quite easy, just a little modification on php.ini file to change the “session.save_path ? directive to point to the NFS share. The main problem with NFS is on high traffic, NFS share is really slow. So synchronisation and data corruption can arrive and ....! ....! Yes it is Using header("Expires: Mon, 26 Jul 2007 05:00:00 GMT"); <?php header("Expires: Mon, 26 Jul 2007 05:00:00 GMT"); ?> www.w3answers.com ....! <?php var_dump(0 == "a"); ?> a) false b) true c) error d) declaration error ANS : true ....!