php_notes

Echo [ echo ]

• echo

Variables [ var ]

• basic var
• define
• global

Arithmetic

• Addition
• Subtraction
• Multiplication
• Division
• Modules -Data type
• Boolean
• x++ and x--

Comparison

Logical Operators

• and : true if x and y true
• or : true if x or y true
• xor : true if x or y true,but not both
• ! : true if x is not true

Arrey

• $name=array("a", "b","c")
• $name[0] = "a"
• $name[1] = "b"

Associative Arrays

• $people = array("David"=>"27", "Amy"=>"21", "John"=>"42");
• $people['Amy'] = "21";

Conditions [ifelse]

• if (condition){---} else {---}
• elif = elseif
• elseif (conditions)

while loop [ while ]

• The do...while loop will always execute the block of code once, check the condition, and repeat the loop as long as the specified condition is true
• $i=0;do {echo "Hai";}while ($i <0);

Switch [ switch ]

Include

• like python import
• php include 'header.php';

forloop

• for (--;--;--){-----}

function

• When using default arguments, any defaults should be on the right side of any non-default arguments; otherwise, things will not work as expected
• function num($a=10) :- if in num parameter not passed, it defaultly take $a=10

$_SERVER

• $_SERVER is an array that includes information such as headers, paths, and script locations. The entries in this array are created by the web server. $_SERVER['SCRIPT_NAME'] returns the path of the current script:
• eg: file name = index.php then,$_SERVER['SCRIPT_NAME'] == index.php
• $_SERVER['HTTP_HOST'] returns the Host header from the current request.