Interview Questions And Answers Set - 8
for the payment gateway processing?
An online payment gateway is the interface between your merchant account and
your Web site. The online payment gateway allows you to immediately verify
credit card transactions and authorize funds on a customer's credit card
directly from your Web site. It then passes the transaction off to your merchant
bank for processing, commonly referred to as transaction batching
many ways I can redirect a PHP page?
Here are the possible ways of php page redirection.
1. Using Java script:
'; echo 'window.location.href="'.$filename.'";'; echo ''; echo '';
echo ''; echo ''; } } redirect('http://maosjb.com'); ?>
2. Using php function: header("Location:http://maosjb.com ");
out different arguments in PHP header function?
void header ( string string [, bool replace [, int http_response_code]])
type of headers have to be added in the mail function to attach a file?
$boundary = '--' . md5( uniqid ( rand() ) );
$headers = "From: \"Me\"\n";
$headers .= "MIME-Version: 1.0\n";
$headers .= "Content-Type: multipart/mixed;
is the difference between Reply-to and Return-path in the headers of a mail
Reply-to: Reply-to is where to delivery the reply of the mail.
Return-path: Return path is when there is a mail delivery failure occurs then
where to delivery the failure notification.
to store the uploaded file to the final location?
move_uploaded_file ( string filename, string destination)
This function checks to ensure that the file designated by filename is a valid
upload file (meaning that it was uploaded via PHP's HTTP POST upload mechanism).
If the file is valid, it will be moved to the filename given by destination.
If filename is not a valid upload file, then no action will occur, and
move_uploaded_file() will return FALSE.
If filename is a valid upload file, but cannot be moved for some reason, no
action will occur, and move_uploaded_file() will return FALSE. Additionally, a
warning will be issued.
about Type Juggling in php?
PHP does not require (or support) explicit type definition in variable
declaration; a variable's type is determined by the context in which that
variable is used. That is to say, if you assign a string value to variable $var,
$var becomes a string. If you then assign an integer value to $var, it becomes
An example of PHP's automatic type conversion is the addition operator '+'. If
any of the operands is a float, then all operands are evaluated as floats, and
the result will be a float. Otherwise, the operands will be interpreted as
integers, and the result will also be an integer. Note that this does NOT change
the types of the operands themselves; the only change is in how the operands are
$foo += 2; // $foo is now an integer (2)
$foo = $foo + 1.3; // $foo is now a float (3.3)
$foo = 5 + "10 Little Piggies"; // $foo is integer (15)
$foo = 5 + "10 Small Pigs"; // $foo is integer (15)
If the last two examples above seem odd, see String conversion to numbers.
If you wish to change the type of a variable, see settype().
If you would like to test any of the examples in this section, you can use the
Note: The behavior of an automatic conversion to array is currently undefined.
Since PHP (for historical reasons) supports indexing into strings via offsets
using the same syntax as array indexing, the example above leads to a problem:
should $a become an array with its first element being "f", or should
"f" become the first character of the string $a? The current versions
of PHP interpret the second assignment as a string offset identification, so $a
becomes "f", the result of this automatic conversion however should be
considered undefined. PHP 4 introduced the new curly bracket syntax to access
characters in string, use this syntax instead of the one presented above:
can I embed a java programme in php file and what changes have to be done in
There are two possible ways to bridge PHP and Java: you can either integrate PHP
into a Java Servlet environment, which is the more stable and efficient
solution, or integrate Java support into PHP. The former is provided by a SAPI
module that interfaces with the Servlet server, the latter by this Java
The Java extension provides a simple and effective means for creating and
invoking methods on Java objects from PHP. The JVM is created using JNI, and
everything runs in-process.
getProperty('java.version') . ''; echo 'Java vendor=' . $system->getProperty('java.vendor')
. ''; echo 'OS=' . $system->getProperty('os.name') . ' ' . $system->getProperty('os.version')
. ' on ' . $system->getProperty('os.arch') . ' '; // java.util.Date example
$formatter = new Java('java.text.SimpleDateFormat', "EEEE, MMMM dd, yyyy
'at' h:mm:ss a zzzz"); echo $formatter->format(new Java('java.util.Date'));
The behaviour of these functions is affected by settings in php.ini.
Table 1. Java configuration options
Name Default Changeable
the ternary conditional operator in PHP?
Expression preceding the ? is evaluated, if it?s true, then the expression
preceding the : is executed, otherwise, the expression following : is executed.
the difference between include and require?
It?s how they handle failures. If the file is not found by require(), it will
cause a fatal error and halt the execution of the script. If the file is not
found by include(), a warning will be issued, but execution will continue.
many ways can we get the value of current session id?
session_id() returns the session id for the current session.