PHP Programming 101

Image sOurce:www.foundationphp.com
PHP was created by Rasmus Lerdorf in 1994 and it was written in C programming language. He created PHP so that he can trace the people who visited his online CV. To make things easier for him to debug his program, he made it into an open source. Then, on June 8, 1995, Lerdorf combined PHP and his own Form Interpreter because of the growing needs of web pages. It was now called as PHP/FI, but generally known as PHP 2.0. Then, in 1997, Andi Gutmans and Zeev Suraski rebuilt the main parser. Before Andi Gutmans and Zeec Suraski rewrote the PHP’s core, PHP was widely known as “Personal Homepage”.

PHP was widely known as “Personal Homepage” until Andi Gutsman and Zeev Suraski Rebuit the main parser of PHP. And so, the acronym PHP was formally changed to PERL Hypertext Preprocessor. Then PHP 3 was released in 1998.

PHP 4 was released in May 2000 with a new core known as the Zend Engine 1.0. In July 2004, PHP 5 was released with the updated Zend Engine 2.0 and new features. PHP 6 was released in October, 20006.

(cont….)

V. Operators in PHP

*Arithmetic Operators*

+ addition
- subtraction
* multiplication
/ division
% modulus (division remainder)
++ increment
– decrement

*Comparison Operators*
== equal to
!= not equal
> greater than
= greater than or equal
<= less than or equal

*Logical Operators*
&& and
|| or
! not

I know its self explanatory…

VI. IF….Else Statements

If (condition)
//*Things to be executed if the answer to the condition is true*//
else
//*Things to be executed if the answer to the condition is false*//

If…else statement is use if the user wants to execute a set of code when the condition is true and another if the condition is not true.

VII. Switch Statement

switch (expression)
{
case 1:
//*code to be executed*//
break;
case 2:
//*code to be executed*//
break;
default:
//*code to be executed*//
break;
}

Switch statement is use if you want to select one of many blocks of code to be executed. this statement is used to avoid long blocks of if…elseif..else.

VIII. Looping Statement

while(condition)
code to be executed;

While statement is used to execute a block of code if and as long as a condition is true

do
{
code to be executed;
}while (condition)

Do—while statement is used to execute a block of code at least once and it will repeat the loop as long as the condition is true.

for each (array as value)
{
code to be executed;
}

For each statement is used to loop through arrays.

I think this is already enough and it has added new knowledge to those who are new in PHP… good luck and happy coding…

image source: www.cass.rrhosting.com

(cont…)
III. PHP Variables

$variablename=value;

Variables are used for storing values such as text string or arrays. And all variables in PHP starts with a ($) dollar sign. There are various rules to be follow before naming a variable. 1) A variable name must start with a letter or an underscore. 2) A variable name can only contain alpha-numeric characters and underscores. Special characters are not allowed. 3) A variable name should not contain spaces.

IV.PHP Strings

$wrd=”Hello World”;
print $wrd;

Strings variables are used for values that contain character strings. The only operator that can be used on string is concatenation denoted by the sign (.) period.

$wrd1=”Hello World”;
$wrd2=”Good day”;
print $wrd1.”".$wrd2

You can count the nos. of string with the function strlen().

Print strlen(“HelloWorld and GoodDay”);

to be continued…

image source: www.php-editors.com