Junior PHP Developer

This is not actually a real function, It is a language construct. So you can use with out parentheses with its argument list.

Example

print('PHP Interview questions');

print 'Job Interview ';

The trim() function removes whitespaces or other predefined characters from both sides of a string.

We can include a file using "include() " or "require()" function with file path as its parameter.

Syntax :

array explode ( string $delimiter , string $string [, int $limit ] );

This function breaks a string into an array. Each of the array elements is a substring of string formed by splitting it on boundaries formed by the string delimiter.

"method" attribute determines how to send the form-data into the server. There are two methods, get and post. The default method is get. This sends the form information by appending it on the URL. Information sent from a form with the POST method is invisible to others and has no limits on the amount of information to send.

PHP syntax resembles Perl and C

If we would like to pass values througn a form or an URL then we need to encode and to decode them using htmlspecialchars() and urlencode().

The result set can be handled using mysql_fetch_array, mysql_fetch_assoc, mysql_fetch_object or mysql_fetch_row.

A static variable is defined within a function only the first time and its value can be modified during function calls as follows:

<!--?php

function testFunction()

{

static $testVariable = 1;

echo $testVariable;

$testVariable++;

}

testFunction(); //1

testFunction(); //2

testFunction(); //3

?-->

1- Combining two variables as follows:

$variable1 = ‘Hello ‘;

$variable2 = ‘World’;

$variable3 = $variable1.$variable2;

Or

2- $variable3 = “$variable1$variable2”;

$variable3 will contain “Hello World”. The first code is faster than the second code especially for large large sets of data.

The session_unregister() function unregister a global variable from the current session and the session_unset() function free all session variables.

The name of the output type have to be specified in parentheses before the variable which is to be cast as follows:

* (int), (integer) – cast to integer

* (bool), (boolean) – cast to boolean

* (float), (double), (real) – cast to float

* (string) – cast to string

* (array) – cast to array

* (object) – cast to object

addslashes function enables us to escape data before storage into the database.

Two methods are possible:

<!--?php echo "Method 1"; print "Method 2"; ?-->

Just use the PHP command line interface (CLI) and specify the file name of the script to be executed as follows:

php script.php

There is a good page in the php manual on the subject, in short mysql_pconnect() makes a persistent connection to the database which means a SQL link that do not close when the execution of your script ends. mysql_connect() provides only for the database new connection while using mysql_pconnect, the function would first try to find a (persistent) link that's already open with the same host, username and password. If one is found, an identifier for it will be returned instead of opening a new connection... the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use.

if ($_FILES["file"]["error"] == 0)

{

move_uploaded_file($_FILES["file"]["tmp_name"],

"upload/" . $_FILES["file"]["name"]);

echo "Stored in: " . "upload/" . $_FILES["file"]["name"];

}

require() includes and evaluates a specific file, while require_once() does that only if it has not been included before (on the same page). So, require_once() is recommended to use when you want to include a file where you have a lot of functions for example. This way you make sure you don't include the file more times and you will not get the "function re-declared" error.

Create session : session_start();

Set value into session : $_SESSION['USER_ID']=1;

Remove data from a session : unset($_SESSION['USER_ID'];