PHP Introduction

PHP Three letters that together constitutes the name of one of the world’s most popular programming languages for Web development, the PHP Hypertext Preprocessor.

Advantage of PHP

Performance
Portability(Platform Independent)
Ease Of Use
Open Source
Third-Party Application Support
Community Support

PHP Environment Start – End

syntax is a way to representation of PHP script.

Basically it gives the primary idea to specify the code format.

It also specify the area of a written code.

The most commonly and effective PHP syntax:

<?php

echo "Welcome to the world of php";

In the given Example

It begin with (< ?php) and End with(? >).

echo statement is used to print the given string. Mandatory closing in(“my statement”)double quotes.

Terminate the script with semicolon because semicolon is known as terminator.

Short or short-open tags look like this:

echo "welcome to the world of php";

HTML script tags:

echo "welcome to the world of php";

</script>

PHP Variables

Variable is nothing it is just name of the memory location.

A Variable is simply a container i.e used to store both numeric and non-numeric information.

Rules for Variable declaration

Variables in PHP starts with a dollar($) sign, followed by the name of the variable.
The variable name must begin with a letter or the underscore character.
A variable name can only contain alphanumeric characters and underscores (A-z, 0-9, and _ )
A variable name should not contain space

Assigning Values to Variables

Assigning a value to a variable in PHP is quite east: use the equality(=) symbol, which also to the PHP’s assignment operators.

This assign value on the right side of the equation to the variable on the left.

A variable is created the moment you assign a value to it:

<?php

$myCar = "K S Ford";

echo $myCar;

Output: K S Ford

PHP Concatenation

<?php

$myCar = "Honda City";

echo $myCar." is riding";

Output:

Honda City is riding

In the above example

Variable($mycar) hold value=”honda city”. Now we wants to concatenate variable with string.

pass this variable($mycar) inside echo statement.

To concatenate this with a string(“is riding”) use dot(.) between variable name and string.

The output will be displayed : Honda City is riding.

Constant in PHP

Constants are PHP container that remain constant and never change
Constants are used for data that is unchanged at multiple place within our program.
Variables are temporary storage while Constants are permanent.
Use Constants for values that remain fixed and referenced multiple times.

Rules for defining constant

Constants are defined using PHP’s define( ) function, which accepts two arguments:
The name of the constant, and its value.
Constant name must follow the same rules as variable names, with one exception the “$” prefix is not required for constant names.

<?php

define('ConstName', 'value');

Example:-

<?php

define('ONE', 100);

define('TWO', 100);

define('SUM',ONE+TWO);

print "Sum of two constant=".SUM;

Output:

Sum of two constant = 200

PHP data types

Data types specify the size and type of values that can be stored.

Variables does not need to be declared ITS DATA TYPE adding a value to it.

PHP is a Loosely Typed Language so here no need to define data type.

To check only data type use gettype( ) function.

To check value, data type and size use var_dump( ) function.

<?php

$num=100;

$fnum=100.0;

$str="Hello";

var_dump($num,$fnum,$str);

Output

int(100) float(100) string(5) “Hello”

Data types in PHP

There are 3 types of DATA TYPE

Scalar(predefined)
Compound(user-defined)
Special type

Scalar(It holds only single value)

Integer
Float/double
String
Boolean

Compound(Multiple values in single variable)

Array
Object

Array Data type

<?php

$arr=array(10,20,30,40,50);

var_dump($arr);

Output

array(5) { [0]=> int(10) [1]=> int(20) [2]=> int(30) [3]=> int(40) [4]=> int(50) }

Object Data type

<?php

class Demo

{

public function show()

{

echo "You Are In method<br/>";

}

$obj= new Demo();

$obj->show();

Output

You Are In method

Special Data types

Null
Resource

Null Data type

The special Data type “NULL” represents a variable with no value

Resource Data Type

The special resource type is not an actual data type. It is the storing of a reference to functions and resources external to PHP.

PHP Form Example

PHP form is used to take input from users. in PHP if you want to take input from keyboard and display the output according to input, in that case you have to use html form.

html form’s have a property : form method in which you have to set either get or post method.

<html>

<head>

<title>form method</title>

</head>

<body>

<h2>Select Your car</h2>

<tr>

<td>Select Your car</td>

<td>

<option value="porsche 911">Porsche 911</option>

<option value="Volkswagen Beetle">Volkswagen Beetle</option>

<option value="Ford Taurus">Ford Taurus</option>

</select>

</td>

</tr>

<tr>

<td>Color:</td>

</td>

</tr>

<tr>

</td>

</tr>

</table">

</form>

</body>

</html>

<?php

error_reporting(1);

$type=$_POST['selType'];

$color=$_POST['txtColor'];

echo "<font color='blue'>Your $color $type is ready. safe driving! </font>";

Output

Run On Browser

Form GET Method

GET method is unsecured method because it display all information on address bar/ url.

By default method is get method. Using GET method limited data sends. GET method is faster way to send data.

When to use GET?

Information sent from a form with the GET method is visible to everyone (all variable names and values are displayed in the URL). GET also has limits on the amount of information to send. The limitation is about 2000 characters. However, because the variables are displayed in the URL, it is possible to bookmark the page. This can be useful in some cases.

GET may be used for sending non-sensitive data.

Enter two number and print the sum of given numbers.

<html>

<head>

<title>get_browser</title>

<?php

error_reporting(1);

$x=$_GET['f'];

$y=$_GET['s'];

$z=$x+$y;

echo "Sum of two number = ".$z;

</head>

<tr>

<td>Enter your first number</td>

</tr>

<tr>

<td>Enter your second number</td>

</tr>

</tr>

</table>

</form>

</body>

</html>

user has to enter the first number, second number

after given the input click on “+” button, and check the output means the sum of two numbers.

can also see the input given by him/her displays on address-bar(URL).

Form POST Method

POST method is secured method because it hides all information.

Using POST method unlimited data sends . POST method is slower method comparatively GET method.

When to use POST?

Information sent from a form with the POST method is invisible to others (all names/values are embedded within the body of the HTTP request) and has no limits on the amount of information to send.

Moreover POST supports advanced functionality such as support for multi-part binary input while uploading files to server.

<html>

<head>

<?php

echo $_POST['n'];

<title>get_browser</title>

</head>

<tr>

<td>Enter your name</td>

</tr>

<tr>

</tr>

</table>

</form>

</body>

</html>

user enters the name inside text box, after entered the name inside text box click on submit button it will display the name entered by user like user enters “Phptpoint” inside the text box the output displays “Phptpoint”.

In this example we have used Form POST method. So the user’s input doesn’t display on address-bar.

How to use HTML Form action

Action is used to give reference/link of another page.

If we want to separate the business logic (PHP script) from Presentation layer (HTML script) then use action Property of Form .

It reduce the complexity of bulk of codes. Because All scripts are separately define on their own page.

Using action property HTML script define on a separate page and Business logic(PHP script) on another separate page.

Create HTML Form with action Property

Save as demo.php

<body>

<tr>

<td>Enter your name</td>

</tr>

<tr>

<td>Enter your age</td>

</tr>

<tr>

</td>

</tr>

</table>

</form>

</body>

Save as Logic.php

<?php

$name=$_POST['n'];

$age = $_POST['a'];

echo "Welcome ".$name,"<br>" .$age;

PHP Operators

Operators are used to perform operations on variables and values.

PHP divides the operators in the following groups:

Arithmetic operators
Assignment operators
Comparison operators
Increment/Decrement operators
Logical operators
String operators
Array operators

Arithmetic Operators

The PHP arithmetic operators are used with numeric values to perform common arithmetical operations, such as addition, subtraction, multiplication etc.

Operator	Name	Example	Result
+	Addition	$x + $y	Sum of $x and $y
-	Subtraction	$x - $y	Difference of $x and $y
*	Multiplication	$x * $y	Product of $x and $y
/	Division	$x / $y	Quotient of $x and $y
%	Modulus	$x % $y	Remainder of $x divided by $y
**	Exponentiation	$x ** $y	Result of raising $x to the $y'th power (Introduced in PHP 5.6)

Assignment Operators

The PHP assignment operators are used with numeric values to write a value to a variable.

The basic assignment operator in PHP is "=". It means that the left operand gets set to the value of the assignment expression on the right.

Assignment	Same as...	Description
x = y	x = y	The left operand gets set to the value of the expression on the right
x += y	x = x + y	Addition
x -= y	x = x - y	Subtraction
x *= y	x = x * y	Multiplication
x /= y	x = x / y	Division
x %= y	x = x % y	Modulus

Comparison Operators

The PHP comparison operators are used to compare two values (number or string):

Operator	Name	Example	Result
==	Equal	$x == $y	Returns true if $x is equal to $y
===	Identical	$x === $y	Returns true if $x is equal to $y, and they are of the same type
!=	Not equal	$x != $y	Returns true if $x is not equal to $y
<>	Not equal	$x <> $y	Returns true if $x is not equal to $y
!==	Not identical	$x !== $y	Returns true if $x is not equal to $y, or they are not of the same type
>	Greater than	$x > $y	Returns true if $x is greater than $y
<	Less than	$x < $y	Returns true if $x is less than $y
>=	Greater than or equal to	$x >= $y	Returns true if $x is greater than or equal to $y
<=	Less than or equal to	$x <= $y	Returns true if $x is less than or equal to $y

Increment / Decrement Operators

The PHP increment operators are used to increment a variable's value.

The PHP decrement operators are used to decrement a variable's value.

Operator	Name	Description
++$x	Pre-increment	Increments $x by one, then returns $x
$x++	Post-increment	Returns $x, then increments $x by one
--$x	Pre-decrement	Decrements $x by one, then returns $x
$x--	Post-decrement	Returns $x, then decrements $x by one

Logical Operators

The PHP logical operators are used to combine conditional statements.

Operator	Name	Example	Result
and	And	$x and $y	True if both $x and $y are true
or	Or	$x or $y	True if either $x or $y is true
xor	Xor	$x xor $y	True if either $x or $y is true, but not both
&&	And	$x && $y	True if both $x and $y are true
\|\|	Or	$x \|\| $y	True if either $x or $y is true
!	Not	!$x	True if $x is not true

String Operators

PHP has two operators that are specially designed for strings.

Operator	Name	Example	Result
.	Concatenation	$txt1 . $txt2	Concatenation of $txt1 and $txt2
.=	Concatenation assignment	$txt1 .= $txt2	Appends $txt2 to $txt1

Array Operators

The PHP array operators are used to compare arrays.

Operator	Name	Example	Result
+	Union	$x + $y	Union of $x and $y
==	Equality	$x == $y	Returns true if $x and $y have the same key/value pairs
===	Identity	$x === $y	Returns true if $x and $y have the same key/value pairs in the same order and of the same types
!=	Inequality	$x != $y	Returns true if $x is not equal to $y
<>	Inequality	$x <> $y	Returns true if $x is not equal to $y
!==	Non-identity	$x !== $y	Returns true if $x is not identical to $y

PHP Conditional Statements

In PHP we have the following conditional statements:

if statement - executes some code if one condition is true
if...else statement - executes some code if a condition is true and another code if that condition is false
if...elseif....else statement - executes different codes for more than two conditions
switch statement - selects one of many blocks of code to be executed

The if Statement

The if statement executes some code if one condition is true.

Syntax

if (condition) {

code to be executed if condition is true;

}

The example below will output "Have a good day!" if the current time (HOUR) is less than 20:

Example

<?php

$t = 10;

if ($t < "20") {

echo "Have a good day!";

}

The if...else Statement

The if....else statement executes some code if a condition is true and another code if that condition is false.

Syntax

if (condition) {

code to be executed if condition is true;

} else {

code to be executed if condition is false;

}

Example

<?php

$t = 10;

if ($t <20) {

echo "Have a good day!";

} else {

echo "Have a good night!";

}

The if...elseif....else Statement

The if....elseif...else statement executes different codes for more than two conditions.

Syntax

if (condition) {

code to be executed if this condition is true;

} elseif (condition) {

code to be executed if this condition is true;

} else {

code to be executed if all conditions are false;

}

Example

<?php

$t = 10;

if ($t <10) {

echo "Have a good morning!";

} elseif ($t < 10) {

echo "Have a good day!";

} else {

echo "Have a good night!";

}

PHP switch Statement

Use the switch statement to select one of many blocks of code to be executed.

Syntax

switch (n) {

case label1:

code to be executed if n=label1;

break;

case label2:

code to be executed if n=label2;

break;

case label3:

code to be executed if n=label3;

break;

...

default:

code to be executed if n is different from all labels;

}

Example

<?php

$favcolor = "red";

switch ($favcolor) {

case "red":

echo "Your favorite color is red!";

break;

case "blue":

echo "Your favorite color is blue!";

break;

case "green":

echo "Your favorite color is green!";

break;

default:

echo "Your favorite color is neither red, blue, nor green!";

}

Loops

Often when you write code, you want the same block of code to run over and over again in a row. Instead of adding several almost equal code-lines in a script, we can use loops to perform a task like this.

In PHP, we have the following looping statements:

while - loops through a block of code as long as the specified condition is true
do...while - loops through a block of code once, and then repeats the loop as long as the specified condition is true
for - loops through a block of code a specified number of times
foreach - loops through a block of code for each element in an array

The PHP while Loop

The while loop executes a block of code as long as the specified condition is true.

Syntax

while (condition is true) {

code to be executed;

}

Example

<?php

$x = 1;

while($x <= 5) {

echo "The number is: $x <br>";

$x++;

}

do...while Loop

The do...while loop will always execute the block of code once, it will then check the condition, and repeat the loop while the specified condition is true.

Syntax

do {

code to be executed;

} while (condition is true);

Example

<?php

$x = 1;

do {

echo "The number is: $x <br>";

$x++;

} while ($x <= 5);

for Loop

The for loop is used when you know in advance how many times the script should run.

Syntax

for (init counter; test counter; increment counter) {

code to be executed;

}

Parameters:

init counter: Initialize the loop counter value
test counter: Evaluated for each loop iteration. If it evaluates to TRUE, the loop continues. If it evaluates to FALSE, the loop ends.
increment counter: Increases the loop counter value

Example

<?php

for ($x = 0; $x <= 10; $x++) {

echo "The number is: $x <br>";

}

foreach Loop

The foreach loop works only on arrays, and is used to loop through each key/value pair in an array.

Syntax

foreach ($array as $value) {

code to be executed;

}

For every loop iteration, the value of the current array element is assigned to $value and the array pointer is moved by one, until it reaches the last array element.

Example

<?php

$colors = array("red", "green", "blue", "yellow");

foreach ($colors as $value) {

echo "$value <br>";

}

Functions

The real power of PHP comes from its functions; it has more than 1000 built-in functions.

PHP User Defined Functions

Besides the built-in PHP functions, we can create our own functions.

A function is a block of statements that can be used repeatedly in a program.

A function will not execute immediately when a page loads.

A function will be executed by a call to the function.

Create a User Defined Function in PHP

A user-defined function declaration starts with the word function:

Syntax

function functionName() {

code to be executed;

}

Note: A function name can start with a letter or underscore (not a number).

Example

<?php

function writeMsg() {

echo "Hello world!";

}

writeMsg(); // call the function

Function Arguments

Information can be passed to functions through arguments. An argument is just like a variable.

Arguments are specified after the function name, inside the parentheses. You can add as many arguments as you want, just separate them with a comma.

Example

<?php

function familyName($fname) {

echo "$fname Chahar.<br>";

}

familyName("pk");

familyName("sk");

familyName("lk");

familyName("vk");

familyName("ak");

function with two arguments ($fname and $year):

<?php

function familyName($fname, $year) {

echo "$fname Chahar. Born in $year <br>";

}

familyName("pk", "1975");

familyName("sk", "1978");

familyName("lk", "1983");

Output:

pk Chahar. Born in 1975

sk Chahar. Born in 1978

lk Chahar. Born in 1983

Functions - Returning values

To let a function return a value, use the return statement:

Example

<?php

function sum($x, $y) {

$z = $x + $y;

return $z;

}

echo "5 + 10 = " . sum(5, 10) . "<br>";

echo "7 + 13 = " . sum(7, 13) . "<br>";

echo "2 + 4 = " . sum(2, 4);

Arrays

An array stores multiple values in one single variable.

An array is a special variable, which can hold more than one value at a time.

In PHP, the array() function is used to create an array:

array();

In PHP, there are three types of arrays:

Indexed arrays - Arrays with a numeric index
Associative arrays - Arrays with named keys
Multidimensional arrays - Arrays containing one or more arrays

Indexed Arrays

There are two ways to create indexed arrays:

The index can be assigned automatically (index always starts at 0), like this:

$players = array("Dhoni", "Raina", "Kohali");

or the index can be assigned manually:

$players[0] = "Dhoni";

$players[1] = "Raina";

$players[2] = "Kohali";

Example

<?php

$players = array("Dhoni", "Raina", "Kohli");

echo "I like " . $players[0] . ", " . $players[1] . " and " . $players[2] . ".";

The count() function is used to return the length (the number of elements) of an array:

Example

<?php

$players = array("Dhoni", "Raina", "Kohli");

echo count($players);

Associative Arrays

Associative arrays are arrays that use named keys that you assign to them.

There are two ways to create an associative array:

$age = array("Peter"=>"35", "Ben"=>"37", "Joe"=>"43");

or:

$age['Peter'] = "35";

$age['Ben'] = "37";

$age['Joe'] = "43";

Example

<?php

$age = array("Peter"=>"35", "Ben"=>"37", "Joe"=>"43");

echo "Peter is " . $age['Peter'] . " years old.";

Multidimensional Arrays

A multidimensional array is an array containing one or more arrays.

PHP understands multidimensional arrays that are two, three, four, five, or more levels deep. However, arrays more than three levels deep are hard to manage for most people.

The dimension of an array indicates the number of indices you need to select an element.

For a two-dimensional array you need two indices to select an element
For a three-dimensional array you need three indices to select an element

Form Validation

The HTML code of the form looks like this:

When the form is submitted, the form data is sent with method="post".

What is the $_SERVER["PHP_SELF"] variable?

The $_SERVER["PHP_SELF"] is a super global variable that returns the filename of the currently executing script.

So, the $_SERVER["PHP_SELF"] sends the submitted form data to the page itself, instead of jumping to a different page. This way, the user will get error messages on the same page as the form.

What is the htmlspecialchars() function?

The htmlspecialchars() function converts special characters to HTML entities. This means that it will replace HTML characters like < and > with < and >. This prevents attackers from exploiting the code by injecting HTML or Javascript code (Cross-site Scripting attacks) in forms.

Display The Error Messages

Then in the HTML form, we add a little script after each required field, which generates the correct error message if needed (that is if the user tries to submit the form without filling out the required fields):

Example

<!DOCTYPE HTML>

<html>

<head>

<style>

.error {color: #FF0000;}

</style>

</head>

<body>

<?php

// define variables and set to empty values

$nameErr = $emailErr = $genderErr = $websiteErr = "";

$name = $email = $gender = $comment = $website = "";

if ($_SERVER["REQUEST_METHOD"] == "POST") {

if (empty($_POST["name"])) {

$nameErr = "Name is required";

} else {

$name = test_input($_POST["name"]);

}

if (empty($_POST["email"])) {

$emailErr = "Email is required";

} else {

$email = test_input($_POST["email"]);

}

if (empty($_POST["website"])) {

$website = "";

} else {

$website = test_input($_POST["website"]);

}

if (empty($_POST["comment"])) {

$comment = "";

} else {

$comment = test_input($_POST["comment"]);

}

if (empty($_POST["gender"])) {

$genderErr = "Gender is required";

} else {

$gender = test_input($_POST["gender"]);

}

function test_input($data) {

$data = trim($data);

$data = stripslashes($data);

$data = htmlspecialchars($data);

return $data;

}

<h2>PHP Form Validation Example</h2>

<p><span class="error">* required field</span></p>

Name: <input type="text" name="name">

E-mail: <input type="text" name="email">

Website: <input type="text" name="website">

Comment: <textarea name="comment" rows="5" cols="40"></textarea>

Gender:

<input type="radio" name="gender" value="female">Female

<input type="radio" name="gender" value="male">Male

<input type="radio" name="gender" value="other">Other

</form>

<?php

echo "<h2>Your Input:</h2>";

echo $name;

echo "<br>";

echo $email;

echo "<br>";

echo $website;

echo "<br>";

echo $comment;

echo "<br>";

echo $gender;

</body>

</html>

Validate Name

The code below shows a simple way to check if the name field only contains letters and whitespace. If the value of the name field is not valid, then store an error message:

$name = test_input($_POST["name"]);

if (!preg_match("/^[a-zA-Z ]*$/",$name)) {

$nameErr = "Only letters and white space allowed";

}

The preg_match() function searches a string for pattern, returning true if the pattern exists, and false otherwise.

PHP - Validate E-mail

The easiest and safest way to check whether an email address is well-formed is to use PHP's filter_var() function.

In the code below, if the e-mail address is not well-formed, then store an error message:

$email = test_input($_POST["email"]);

if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {

$emailErr = "Invalid email format";

}

PHP - Validate URL

The code below shows a way to check if a URL address syntax is valid (this regular expression also allows dashes in the URL). If the URL address syntax is not valid, then store an error message:

$website = test_input($_POST["website"]);

if (!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website)) {

$websiteErr = "Invalid URL";

}

Example

<!DOCTYPE HTML>

<html>

<head>

<style>

.error {color: #FF0000;}

</style>

</head>

<body>

<?php

// define variables and set to empty values

$nameErr = $emailErr = $genderErr = $websiteErr = "";

$name = $email = $gender = $comment = $website = "";

if ($_SERVER["REQUEST_METHOD"] == "POST") {

if (empty($_POST["name"])) {

$nameErr = "Name is required";

} else {

$name = test_input($_POST["name"]);

// check if name only contains letters and whitespace

if (!preg_match("/^[a-zA-Z ]*$/",$name)) {

$nameErr = "Only letters and white space allowed";

}

if (empty($_POST["email"])) {

$emailErr = "Email is required";

} else {

$email = test_input($_POST["email"]);

// check if e-mail address is well-formed

if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {

$emailErr = "Invalid email format";

}

if (empty($_POST["website"])) {

$website = "";

} else {

$website = test_input($_POST["website"]);

// check if URL address syntax is valid

if (!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website)) {

$websiteErr = "Invalid URL";

}

if (empty($_POST["comment"])) {

$comment = "";

} else {

$comment = test_input($_POST["comment"]);

}

if (empty($_POST["gender"])) {

$genderErr = "Gender is required";

} else {

$gender = test_input($_POST["gender"]);

}

function test_input($data) {

$data = trim($data);

$data = stripslashes($data);

$data = htmlspecialchars($data);

return $data;

}

<h2>PHP Form Validation Example</h2>

<p><span class="error">* required field</span></p>

Name: <input type="text" name="name">

E-mail: <input type="text" name="email">

Website: <input type="text" name="website">

Comment: <textarea name="comment" rows="5" cols="40"></textarea>

Gender:

<input type="radio" name="gender" value="female">Female

<input type="radio" name="gender" value="male">Male

<input type="radio" name="gender" value="other">Other

</form>

<?php

echo "<h2>Your Input:</h2>";

echo $name;

echo "<br>";

echo $email;

echo "<br>";

echo $website;

echo "<br>";

echo $comment;

echo "<br>";

echo $gender;

</body>

</html>

PHP Date() Function

The PHP date() function formats a timestamp to a more readable date and time.

Syntax

date(format,timestamp)

Parameter	Description
format	Required. Specifies the format of the timestamp
timestamp	Optional. Specifies a timestamp. Default is the current date and time

Get a Simple Date

The required format parameter of the date() function specifies how to format the date (or time).

Here are some characters that are commonly used for dates:

d - Represents the day of the month (01 to 31)
m - Represents a month (01 to 12)
Y - Represents a year (in four digits)
l (lowercase 'L') - Represents the day of the week

Example

<?php

echo "Today is " . date("Y/m/d") . "<br>";

echo "Today is " . date("Y.m.d") . "<br>";

echo "Today is " . date("Y-m-d") . "<br>";

echo "Today is " . date("l");

Simple Time

Here are some characters that are commonly used for times:

h - 12-hour format of an hour with leading zeros (01 to 12)
i - Minutes with leading zeros (00 to 59)
s - Seconds with leading zeros (00 to 59)
a - Lowercase Ante meridiem and Post meridiem (am or pm)

The example below outputs the current time in the specified format:

Example

<?php

echo "The time is " . date("h:i:sa");

Time Zone

If the time you got back from the code is not the right time, it's probably because your server is in another country or set up for a different timezone.

Example

<?php

date_default_timezone_set("America/New_York");

echo "The time is " . date("h:i:sa");

Date With PHP mktime()

The optional timestamp parameter in the date() function specifies a timestamp. If you do not specify a timestamp, the current date and time will be used (as shown in the examples above).

The mktime() function returns the Unix timestamp for a date. The Unix timestamp contains the number of seconds between the Unix Epoch (January 1 1970 00:00:00 GMT) and the time specified.

Syntax

mktime(hour,minute,second,month,day,year)

<?php

$d=mktime(11, 14, 54, 8, 12, 2014);

echo "Created date is " . date("Y-m-d h:i:sa", $d);

PHP 5 Date/Time Functions

Function	Description
checkdate()	Validates a Gregorian date
date_add()	Adds days, months, years, hours, minutes, and seconds to a date
date_create_from_format()	Returns a new DateTime object formatted according to a specified format
date_create()	Returns a new DateTime object
date_date_set()	Sets a new date
date_default_timezone_get()	Returns the default timezone used by all date/time functions
date_default_timezone_set()	Sets the default timezone used by all date/time functions
date_diff()	Returns the difference between two dates
date_format()	Returns a date formatted according to a specified format
date_get_last_errors()	Returns the warnings/errors found in a date string
date_interval_create_from_date_string()	Sets up a DateInterval from the relative parts of the string
date_interval_format()	Formats the interval
date_isodate_set()	Sets the ISO date
date_modify()	Modifies the timestamp
date_offset_get()	Returns the timezone offset
date_parse_from_format()	Returns an associative array with detailed info about a specified date, according to a specified format
date_parse()	Returns an associative array with detailed info about a specified date
date_sub()	Subtracts days, months, years, hours, minutes, and seconds from a date
date_sun_info()	Returns an array containing info about sunset/sunrise and twilight begin/end, for a specified day and location
date_sunrise()	Returns the sunrise time for a specified day and location
date_sunset()	Returns the sunset time for a specified day and location
date_time_set()	Sets the time
date_timestamp_get()	Returns the Unix timestamp
date_timestamp_set()	Sets the date and time based on a Unix timestamp
date_timezone_get()	Returns the time zone of the given DateTime object
date_timezone_set()	Sets the time zone for the DateTime object
date()	Formats a local date and time
getdate()	Returns date/time information of a timestamp or the current local date/time
gettimeofday()	Returns the current time
gmdate()	Formats a GMT/UTC date and time
gmmktime()	Returns the Unix timestamp for a GMT date
gmstrftime()	Formats a GMT/UTC date and time according to locale settings
idate()	Formats a local time/date as integer
localtime()	Returns the local time
microtime()	Returns the current Unix timestamp with microseconds
mktime()	Returns the Unix timestamp for a date
strftime()	Formats a local time and/or date according to locale settings
strptime()	Parses a time/date generated with strftime()
strtotime()	Parses an English textual datetime into a Unix timestamp
time()	Returns the current time as a Unix timestamp
timezone_abbreviations_list()	Returns an associative array containing dst, offset, and the timezone name
timezone_identifiers_list()	Returns an indexed array with all timezone identifiers
timezone_location_get()	Returns location information for a specified timezone
timezone_name_from_ abbr()	Returns the timezone name from abbreviation
timezone_name_get()	Returns the name of the timezone
timezone_offset_get()	Returns the timezone offset from GMT
timezone_open()	Creates new DateTimeZone object
timezone_transitions_get()	Returns all transitions for the timezone
timezone_version_get()	Returns the version of the timezone db

PHP 5 Predefined Date/Time Constants

Constant	Description
DATE_ATOM	Atom (example: 2005-08-15T16:13:03+0000)
DATE_COOKIE	HTTP Cookies (example: Sun, 14 Aug 2005 16:13:03 UTC)
DATE_ISO8601	ISO-8601 (example: 2005-08-14T16:13:03+0000)
DATE_RFC822	RFC 822 (example: Sun, 14 Aug 2005 16:13:03 UTC)
DATE_RFC850	RFC 850 (example: Sunday, 14-Aug-05 16:13:03 UTC)
DATE_RFC1036	RFC 1036 (example: Sunday, 14-Aug-05 16:13:03 UTC)
DATE_RFC1123	RFC 1123 (example: Sun, 14 Aug 2005 16:13:03 UTC)
DATE_RFC2822	RFC 2822 (Sun, 14 Aug 2005 16:13:03 +0000)
DATE_RSS	RSS (Sun, 14 Aug 2005 16:13:03 UTC)
DATE_W3C	World Wide Web Consortium (example: 2005-08-14T16:13:03+0000)