Post on 17-Dec-2015
transcript
Outline• What is PHP?
• History of PHP
• Why PHP ?
• What is PHP file?
• What you need to start using PHP ?
• Syntax PHP code .
• echo & print Statement
• Variables.
• Data Types.
• Constants &Operators.
• Conditional Statements & Loops.
What is PHP?
Personal Homepage Tools/Form Interpreter
PHP is a Server-side Scripting Language designed
specifically for the Web.
An open source language
PHP code can be embedded within an HTML page,
which will be executed each time that page is
visited.
What is PHP? (cont’d)
• Interpreted language, scripts are parsed at run-time
rather than compiled beforehand
• Executed on the server-side
• Source-code not visible by client
• ‘View Source’ in browsers does not display the PHP code
• Various built-in functions allow for fast development
• Compatible with many popular databases
History of PHP PHP (PHP: Hypertext Preprocessor) was created by Rasmus Lerdorf in 1994. It was
initially developed for HTTP usage logging and server-side form generation in Unix.
PHP 2 (1995) transformed the language into a Server-side embedded scripting
language. Added database support, file uploads, variables, arrays, recursive
functions, conditionals, iteration, regular expressions, etc.
PHP 3 (1998) added support for ODBC data sources, multiple platform support,
email protocols (SNMP,IMAP), and new parser written by Zeev Suraski and Andi
Gutmans .
PHP 4 (2000) became an independent component of the web server for added
efficiency. The parser was renamed the Zend Engine. Many security features were
added.
PHP 5 (2004) adds Zend Engine II with object oriented programming, robust XML
support using the libxml2 library, SOAP extension for interoperability with Web
Services, SQLite has been bundled with PHP
Why PHP ?
PHP runs on different platforms (Windows, Linux, Unix, Mac
OS X, etc.)
PHP is compatible with almost all servers used today
(Apache, IIS, etc.)
PHP has support for a wide range of databases
PHP is free. Download it from the official PHP resource:
www.php.net
PHP is easy to learn and runs efficiently on the server side
What does PHP code look like?
• Structurally similar to C/C++
• Supports procedural and object-oriented
paradigm (to some degree)
What Can PHP Do? PHP can generate dynamic page content
PHP can create, open, read, write, and close files on the server
PHP can collect form data
PHP can send and receive cookies
PHP can add, delete, modify data in your database
PHP can restrict users to access some pages on your website
PHP can encrypt data
With PHP you are not limited to output HTML. You can output
images, PDF files, and even Flash movies. You can also output
any text, such as XHTML and XML
What is a PHP File?
PHP files can contain text, HTML, JavaScript
code, and PHP code
PHP code are executed on the server, and the
result is returned to the browser as plain
HTML
PHP files have a default file extension of
".php”
What you need to start using PHP ?
Installation
You will need
1. Web server ( Apache )
2. PHP ( version 5.3)
3. Database ( MySQL 5 )
4. Text editor (Notepad)
5. Web browser (Firefox )
6. www.php.net/manual/ en/install.php
Syntax PHP code
A PHP script can be placed anywhere in the document.
A PHP script starts with
<?php and ends with ?>
Syntax PHP code
• Standard Style :
<?php …… ?>
• Short Style:
<? … ?>
• Script Style:
<SCRIPT LANGUAGE=‘php’> </SCRIPT>
• ASP Style:
<% echo “Hello World!”; %>
Echo
The PHP command ‘echo’ is used to output the
parameters passed to it .
The typical usage for this is to send data to the client’s
web-browser
Syntax : void echo (string arg1 [, string argn...])
In practice, arguments are not passed in parentheses
since echo is a language construct rather than an actual
function
print is not actually a real function (it is a
language construct) so you are not
required to use parentheses with its
argument list.<?php
print("Hello World");?>
Echo Vs Print
Improve this chart Echo Print
Parameters: echo can take more than one
parameter when used without
parentheses. The syntax is echo
expression [, expression[, expression]
... ]. Note that echo ($arg1,$arg2) is
invalid.
print only takes one parameter.
Return value: echo does not return any value print always returns 1 (integer)
Syntax: void echo ( string $arg1 [, string
$... ] )
int print ( string $arg )
What is it?: In PHP, echo is not a function but a
language construct.
In PHP, print is not a really function
but a language construct. However, it
behaves like a function in that it
returns a value.
Variables As with algebra, PHP variables can be used to hold values
(x=5) or expressions (z=x+y).
Variable can have short names (like x and y) or more
descriptive names (age, carname, totalvolume).
Rules for PHP variables:
A variable starts with the $ sign, followed by the name of
the variable
Variables A variable name must begin with a letter or the underscore
character
A variable name can only contain alpha-numeric characters
and underscores (A-z, 0-9, and _ )
A variable name should not contain spaces
Variable names are case sensitive ($y and $Y are two
different variables)
Variables Case-sensitive ($Foo != $foo != $fOo)
Global and locally-scoped variables
Global variables can be used anywhere
Local variables restricted to a function or class
Certain variable names reserved by PHP
Form variables ($_POST, $_GET)
Server variables ($_SERVER)
Creating (Declaring) Variables
PHP has no command for declaring a variable.
A variable is created the moment you first assign a value to
it:
After the execution of the statements above, the
variable txt will hold the value Hello world!, and the
variable xwill hold the value 5.
Note: When you assign a text value to a variable, put
quotes around the value.
$txt="Hello world!";$x=5;
PHP is a Loosely Typed Language
In the example above, notice that we did not have to tell
PHP which data type the variable is.
PHP automatically converts the variable to the correct data
type, depending on its value.
In a strongly typed programming language, we will have to
declare (define) the type and name of the variable before
using it.
Variables<?php
$name = 'elijah'; $yearborn = 1975; $currentyear = 2005;$age = $currentyear - $yearborn; echo ("$name is $age years old.");
?>
Variables
<?php $name = “Ali"; // declaration ?>
<html>
<head> <title>A simple PHP document</title> </head>
<body style = "font-size: 2em">
<p> <strong>
<!-- print variable name’s value -->
Welcome to PHP, <?php echo( "$name" ); ?>!
</strong> </p>
</body>
</html>
PHP Variable Scopes
The scope of a variable is the part of the script where the
variable can be referenced/used.
PHP has four different variable scopes:
local
global
static
Parameter
- In chapter function we will talk about theme.
String Variables in PHP
string variables are used for values that contain characters.
After we have created a string variable we can manipulate it. A
string can be used directly in a function or it can be stored in a
variable.
In the example below, we create a string variable called txt, then
we assign the text "Hello world!" to it. Then we write the value of
the txt variable to the output:<?php
$txt="Hello world!";echo $txt;
?>
PHP strings can be specified in four ways Single quoted strings will display things almost completely "as is." Variables
and most escape sequences will not be interpreted. The exception is that to
display a literal single quote, you can escape it with a back slash \', and to
display a back slash, you can escape it with another backslash \\ (So yes,
even single quoted strings are parsed).
<?php$txt = ‘my string ‘;
echo $txt; // my string
?>
<?php$txt = ‘my string
‘;
echo ‘$txt’; // $txt
?>
PHP strings can be specified in four ways Double quote strings will display a host of escaped characters (including
some regexes), and variables in the strings will be evaluated. An important
point here is that you can use curly braces to isolate the name of the
variable you want evaluated. For example let's say you have the
variable $type and you what to echo "The $types are" That will look for the
variable $types. To get around this use echo "The {$type}s are" You can
put the left brace before or after the dollar sign. Take a look at
string parsing to see how to use array variables and such.
<?php$txt = “my string”;
echo $txt; // my string
?>
<?php$txt = “my string “;
echo “$txt”; // my string
?>
PHP strings can be specified in four ways Heredoc string syntax works like double quoted strings. It starts with <<<.
After this operator, an identifier is provided, then a newline. The string itself
follows, and then the same identifier again to close the quotation. You don't
need to escape quotes in this syntax.
Nowdoc (since PHP 5.3.0) string syntax works essentially like single quoted
strings. The difference is that not even single quotes or backslashes have
to be escaped. A nowdoc is identified with the same <<< sequence used
for heredocs, but the identifier which follows is enclosed in single quotes,
e.g. <<<'EOT'. No parsing is done in nowdoc.
PHP strings can be specified in four ways Heredoc <?php
$name='MyName';echo <<<EOTMy name is "$name".I am printing some A Now,I am printing some {A}.This should print a capital 'A': \x41EOT;?>
My name is "MyName". I am printing some A Now,I am printing some {A}. This should print a capital 'A': A
PHP strings can be specified in four ways Nowdoc <?php
$name='MyName';echo <<<'EOT'My name is "$name".I am printing some A Now,I am printing some {A}.This should print a capital 'A': \x41EOT;
?>
My name is "$name". I am printing some A Now, I am printing some {A}. This should print a capital 'A': \x41
Single & Double Quotes
<?php
$word = ‘ World’;
echo “ Hello $word <br>”;
echo ‘ Hello $word <br>’;
?>
Comments in PHP
• // or # for single line
• /* */ for multiline
• /*
this is my comment one
this is my comment two
this is my comment three
*/
Whitespace
• You cant have any whitespace between <?
and php.
• You cant break apart keywords (e.g :whi
le,func tion,fo r)
• You cant break apart varible names and
function names (e.g:$var name,function f 2)
The PHP Concatenation Operator
here is only one string operator in PHP.
The concatenation operator (.) is used to join two string values
together.
The example below shows how to concatenate two string variables
together:
<?php$txt1="Hello!";$txt2=" world !";echo $txt1 . " " . $txt2; // Hello world !
?>
The PHP Concatenation Operator
<?php
$string1=“Hello”;
$string2=“PHP”;
$string3=$string1 . “ ” . $string2;
Print $string3;
?>
Hello PHP
Escaping the Character
• If the string has a set of double quotation marks
that must remain visible, use the \ [backslash]
before the quotation marks to ignore and display
them.<?php
$heading="\"Computer Science\""."<br>";
$heading1=@"Computer Science";
echo $heading;
echo $heading1;
?>
"Computer Science"Computer Science
Example
• Notice how echo ‘5x5=$foo’ outputs $foo rather than replacing it with 25
• Strings in single quotes (‘ ’) are not interpreted or evaluated by PHP
• This is true for both variables and character escape-sequences (such as “\n” or “\\”)
<?php
$foo = 25; // Numerical variable
$bar = “Hello”; // String variable
echo $bar; // Outputs Hello
echo $foo,$bar; // Outputs 25Hello
echo “5x5=”,$foo; // Outputs 5x5=25
echo “5x5=$foo”;// Outputs 5x5=25
echo ‘5x5=$foo’; // Outputs 5x5=$foo
?>
Data type
Data type Description int,
integer Whole numbers (i.e., numbers without a decimal point).
float, double
Real numbers (i.e., numbers containing a decimal point).
string Text enclosed in either single ('') or double ("") quotes. bool,
Boolean True or false.
array Group of elements of the same type. object Group of associated data and methods.
Resource An external data source. NULL No value.
Get type gettype — Get the type of a variable Returns the type of the PHP variable var.
<?php$a = 1;$b = 1.2;$c = "abc";echo gettype($a)."<br>";echo gettype($b)."<br>";echo gettype($c)."<br>";?>
integerdoublestring
Set type
<?php
$foo = "5bar"; // string
$bar = true; // boolean
settype($foo, "integer"); // $foo is now 5 (integer)
settype($bar, "string"); // $bar is now "1" (string)
?>
Set type<?php
$testString = “10.2abc”;
// call function settype to convert variable
// testString to different data types
print( "$testString" );
settype( $testString, "double" );
print( " as a double is $testString <br />" );
print( "$testString" );
settype( $testString, "integer" );
print( " as an integer is $testString <br />" );
settype( $testString, "string" );
print( "Converting back to a string results in
$testString <br /><br />" );
?>
10.2abc as a double is 10.2 10.2 as an integer is 10 Converting back to a string results in 10
Casting Data type
<?php
$data = "98.6 degrees";
echo "Now using type casting instead: <br>";
echo "As a string - ".(string) $data ;
echo "<br> As a double - ".(double) $data;
echo "<br> As an integer - ".(integer) $data;
?>
Now using type casting instead: As a string - 98.6 degreesAs a double - 98.6As an integer - 98
Casting Data type
<?php
$data = "98.6 degrees";
echo "Now using type casting instead: <br>";
echo "As a string - ".(string) $data ;
echo "<br> As a double - ".(double) $data;
echo "<br> As an integer - ".(integer) $data;
?>
$variable = (datatype) $variable or value
Casting Data type
<?php
$a = “ 12.4 abc”
echo (int) $a;
echo (double) ($a);
echo (float) ($a);
echo (string) ($a);
?>
PHP Operators
• The assignment operator = is used to assign values to variables in PHP.
• The arithmetic operator + is used to add values together in PHP.
• Assignment operators Syntactical shortcuts Before being assigned values, variables have
value undef• Constants
Named values define function
PHP Operators
• Arithmetic Operators• Assignment Operators• Incrementing/Decrementing
Operators• Comparison Operators• Logical Operators
Arithmetic OperatorsOperator Name Description Example Result
x + y Addition Sum of x and y 2 + 2 4
x - y Subtraction Difference of x and y 5 - 2 3
x * y Multiplication Product of x and y 5 * 2 10
x / y Division Quotient of x and y 15 / 5 3
x % y Modulus Remainder of x divided by y 5 % 210 % 810 % 2
120
- x Negation Opposite of x - 2
a . b Concatenation Concatenate two strings "Hi" . "Ha" HiHa
Assignment Operators
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
a .= b a = a . b Concatenate two strings
Arithmetic Operations
• $a - $b // subtraction• $a * $b // multiplication• $a / $b // division• $a += 5 // $a = $a+5 Also works for *= and /=
<?php$a=15;$b=30;$total=$a+$b;echo $total;
echo“<p><h1>$total</h1>”;// total is 45
?>
Incrementing/Decrementing Operators
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
Arithmetic Operations<?php
$a =1; echo $a++; // output 1,$a is now equal to 2 echo ++$a; // output 3,$a is now equal to 3
echo --$a; // output 2,$a is now equal to 2 echo $a--; // output 2,$a is now equal to 1
?>
Arithmetic Operations
<?php
$num1 = 10;
$num2 =20;
// addition
echo $num1+$mum2 . ‘<br>’;
//subtraction
echo $num1 - $num2 . ‘<br>’;
// multiplication
?>
Arithmetic Operations<?php
// Multiplication
echo $num1* $num2 . ‘<br>’;
// Division
Echo $num1/num2 . ‘<br>’ ;
//increment
$num1++;
$Num2--;
Echo $num1;
?>
Dumps information about a variable
This function displays structured information about one or more
expressions that includes its type and value. Arrays and objects are
explored recursively with values indented to show structure.
void var_dump ($expression [,... ] )
<?php
$b = 3.1;$c = true;var_dump($b);var_dump($c);//or var_dump($b,$c);
?>
float 3.1 boolean true
Comparison Operators
Operator Name Description Example
x == y Equal True if x is equal to y 5==8 returns false
x === y Identical True if x is equal to y, and they are of same type
5==="5" returns false
x != y Not equal True if x is not equal to y 5!=8 returns true
x <> y Not equal True if x is not equal to y 5<>8 returns true
x !== y Not identical True if x is not equal to y, or they are not of same type
5!=="5" returns true
x > y Greater than True if x is greater than y 5>8 returns false
x < y Less than True if x is less than y 5<8 returns true
x >= y Greater than or equal to
True if x is greater than or equal to y 5>=8 returns false
x <= y Less than or equal to
True if x is less than or equal to y 5<=8 returns true
Comparison Operators
<?php
var_dump(0 == "a"); // 0 == 0 -> true
var_dump("1" != "01"); // 1 != 1 -> false
var_dump("10" == "1e1"); // 10 == 10 -> true
var_dump("10" == "1ee1"); // 10 == 1 -> false
var_dump(100 === "100"); // 100 == 100 -> false
var_dump("100" === "100"); // 100 == 100 -> true
?>
boolean true boolean false boolean true boolean false boolean false boolean true
Logical Operators
Operator Name Description Example
x and y And True if both x and y are true x=6y=3
(x < 10 and y > 1) returns true
x or y Or True if either or both x and y are true x=6y=3
(x==6 or y==5) returns true
x xor y Xor True if either x or y is true, but not both
x=6y=3
(x==6 xor y==3) returns false
x && y And True if both x and y are true x=6y=3
(x < 10 && y > 1) returns true
x || y Or True if either or both x and y are true x=6y=3
(x==5 || y==5) returns false
! x Not True if x is not true x=6y=3
!(x==y) returns true
Logical Operators
<?php
$a = (false && true);
$b = (true || false);
$c = (false and flase);
$d = (true or true);
$e = false || true;
$f = false or true;
var_dump($e, $f);
$g = true && false;
$h = true and false;
var_dump($g, $h);
?>
boolean true boolean false boolean false boolean true
Define function - constant VALUE
Variable name as string : the name of variable in single or
double quotation .
<?phpdefine(‘variable ’,10);echo variable ; //10
?>
define( variable name as string , value );
Define function - constant VALUE
<?php
$a = 5;
print( "The value of variable a is $a <br />" );
// define constant VALUE
define( "VALUE", 5 );
// add constant VALUE to variable $a
$a = $a + VALUE;
print( "Variable a after adding constant VALUE
is $a <br />" );
Define function - constant VALUE
// multiply variable $a by 2
$a *= 2;
print( "Multiplying variable a by 2 yields $a <br />" );
// test if variable $a is less than 50
if ( $a < 50 )
print( "Variable a is less than 50 <br />" );
// add 40 to variable $a
$a += 40;
print( "Variable a after adding 40 is $a <br />" );
// test if variable $a is 50 or less
if ( $a < 51 )
print( "Variable a is still 50 or less<br />" );
// test if variable $a is between 50 and 100, inclusive
elseif ( $a < 101 )
print( "Variable a is now between 50 and 100, inclusive<br />" );
else
print( "Variable a is now greater than 100<br />" );
// print an uninitialized variable
print( "Using a variable before initializing:
$nothing <br />" );
// add constant VALUE to an uninitialized variable
$test = $num + VALUE;
print( "An uninitialized variable plus constant
VALUE yields $test <br />" );
// add a string to an integer
$str = "3 dollars";
$a += $str;
print( "Adding a string to variable a yields $a
<br />" );
?>
Define function - constant VALUE
Referencing Operators We know the assignment operators work by value ,by copy the
value to other expression ,if the value in right hand change the value
in left is not change .
Ex:
<?php
$a =10;
$b =$a;
$b =20
Echo $a; // 10
?>
Referencing Operators
But we can change the value of variable $a by the reference , that
mena connect right hand to left hand ,
Example:
<?php
$a =10;
$b = &$a;
$b= 20;
echo $a; // 20
?>
PHP Conditional Statements
Very often when you write code, you want to perform different
actions for different decisions. You can use conditional
statements in your code to do this.
In PHP we have the following conditional statements: if statement - executes some code only if a specified condition is true
if...else statement - executes some code if a condition is true and
another code if the condition is false
if...else if....else statement - selects one of several blocks of code to
be executed
switch statement - selects one of many blocks of code to be executed
The if Statement
• The if statement is used to execute some code only if a specified
condition is true.
<?php$t=5;if ($t<10) { echo "hello john"; }?>
hello john
if (condition) { code to be executed if condition is true; }
The if...else Statement
• Use the if....else statement to execute some code if a condition is
true and another code if the condition is false.
if (condition) { code to be executed if condition is true; }else { code to be executed if condition is false; }
The if...else Statement
<?php$t=55;if ($t<20) { echo "Have a good day!"; }else { echo "Have a good night!"; }?>
Have a good night!
The if...else if....else Statement
• Use the if....else if...else statement to select one of several blocks
of code to be executed. if (condition) { code to be executed if condition is true; }else if (condition) { code to be executed if condition is true; }else { code to be executed if condition is false; }
The if...else if....else Statement
<?php$t=7;if ($t<10) { echo "Have a good morning!"; }else if ($t<20) { echo "Have a good day!"; }else { echo "Have a good night!"; }?>
Have a good morning!
The switch Statement
• Use the switch statement to select one of many blocks of code to
be executed.
switch (n){case label1: code to be executed if n=label1; break;case label2: code to be executed if n=label2; break;default: code to be executed if n is different from both label1 and label2;}
The switch Statement<?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, or green!";}?>
Your favorite color is red!
PHP Loops
• Loops execute a block of code a specified number of times, or
while a specified condition is true.
• In PHP, we have the following looping statements:
• while - loops through a block of code while a specified
condition is true
• do...while - loops through a block of code once, and then
repeats the loop as long as a 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 while Loop• The while loop executes a block of code while a condition is true.
while (condition) { code to be executed; }
<?php$i=1;while($i<=5) { echo "The number is " . $i . "<br>"; $i++; }?>
The number is 1The number is 2The number is 3The number is 4The number is 5
The do...while Statement
• The do...while statement will always execute the block of code
once, it will then check the condition, and repeat the loop while
the condition is true.
do { code to be executed; }while (condition);<?php
$i=1;do { $i++; echo "The number is " . $i . "<br>"; }while ($i<=5);?>
The number is 2The number is 3The number is 4The number is 5The number is 6
The do...while Statement
<?php$i=1;do { $i++; echo "The number is " . $i . "<br>"; }while ($i<=5);?> The number is 2
The number is 3The number is 4The number is 5The number is 6
The for Loop
• The for loop is used when you know in advance how many times
the script should run.
• Parameters:
• init: Mostly used to set a counter (but can be any code to be
executed once at the beginning of the loop)
for (init; condition; increment) { code to be executed; }
The for Loop
• condition: Evaluated for each loop iteration. If it
evaluates to TRUE, the loop continues. If it evaluates to
FALSE, the loop ends.
• increment: Mostly used to increment a counter (but
can be any code to be executed at the end of the
iteration)
• Note: The init and increment parameters above can
be empty or have multiple expressions (separated
by commas).
The for Loop
<?phpfor ($i=1; $i<=5; $i++) { echo "The number is " . $i . "<br>"; }?> The number is 1
The number is 2The number is 3The number is 4The number is 5
The foreach Loop
• The foreach loop is used to loop through arrays.
• We well talk about this in chapter array
Isset Function
• bool isset ( $var )
• Determine if a variable is set and is not NULL.
• If a variable has been unset with unset(), it will no longer be
set. isset() will return FALSE if testing a variable that has been
set to NULL. Also note that a NULLbyte ("\0") is not equivalent to
the PHP NULL constant.
• If multiple parameters are supplied then isset() will
return TRUE only if all of the parameters are set. Evaluation goes
from left to right and stops as soon as an unset variable is
encountered.
Isset Function
<?php
$var = '';
// This will evaluate to TRUE so the text will be printed.
if (isset($var))
{
echo "This var is set so I will print.";
}
?>
Unset Function
• void unset ( $var)
• unset() destroys the specified variables.
• The behavior of unset() inside of a function can vary depending
on what type of variable you are attempting to destroy.
• If a globalized variable is unset() inside of a function, only the
local variable is destroyed. The variable in the calling environment
will retain the same value as before unset() was called.
Goto<?php
goto a;echo 'Foo'; a:echo 'Bar';?>
<?phpfor($i=0,$j=50; $i<100; $i++) { while($j--) { if($j==17) goto end; } }echo "i = $i";end:echo 'j hit 17';?>
if/else if/else statement
<?php
if ($foo == 0) {
echo ‘The variable foo is equal to 0’;
}
else if (($foo > 0) && ($foo <= 5)) {
echo ‘The variable foo is between 1 and 5’;
}
else {
echo ‘The variable foo is equal to ‘.$foo;
}
?>
Switch Statment
<?php$count=0;switch($count){
case 0:echo “hello PHP3. ”;
break;case 1:
echo “hello PHP4. ”;break; default:
echo “hello PHP5. ”;break;
}
?>
hello PHP3
Switch - Example<?php
$total = 0;
$i = 2;
switch($i) {
case 6: $total = 99; break;
case 1: $total += 1;break;
case 2:$total += 2;break;
case 3: $total += 3; ;break;
case 4:$total += 4; break;
default : $total += 5;break;
}
echo $total;
?>
2
For Loop
<?php$count=0;for($count = 0;$count <3,$count++){
Print “hello PHP. ”;}?>
hello PHP. hello PHP. hello PHP.
For-Example
<?php$brush_price = 5; echo "<table border=\"1\" align=\"center\">"; echo "<tr><th>Quantity</th>"; echo "<th>Price</th></tr>";
for ( $counter = 10; $counter <= 100; $counter += 10) {
echo "<tr><td>"; echo $counter; echo "</td><td>"; echo $brush_price * $counter; echo "</td></tr>";
} echo "</table>";?>
While Loop
<?php$count=0;while($count<3){
echo “hello PHP. ”;$count += 1;// $count = $count + 1;// or// $count++;
}?>
hello PHP. hello PHP. hello PHP.
Do ... While Loop
<?php$count=0;do{echo “hello PHP. ”;
$count += 1;// $count = $count + 1;// or// $count++;
}while($count<3);?>
hello PHP. hello PHP. hello PHP.
For..If
<?php
$rows = 4;
echo '<table><tr>';
for($i = 0; $i < 10; $i++){
echo '<td>' . $i . '</td>';
if(($i + 1) % $rows == 0){
echo '</tr><tr>';
}
}
echo '</tr></table>';
?>
For
<?php//this is a different way to use the 'for'//Essa é uma maneira diferente de usar o 'for'for($i = $x = $z = 1; $i <= 10;$i++,$x+=2,$z=&$p){ $p = $i + $x; echo "\$i = $i , \$x = $x , \$z = $z <br />"; }
?>
Nested For
<?php for($a=0;$a<10;$a++){ for($b=0;$b<10;$b++){ for($c=0;$c<10;$c++){ for($d=0;$d<10;$d++){ echo $a.$b.$c.$d.", "; } } } } ?>
While - Switch
<?php$i = 0;
while (++$i) { switch ($i) { case 5: echo "At 5<br />\n"; break 1; /* Exit only the switch. */ case 10: echo "At 10; quitting<br />\n"; break 2; /* Exit the switch and the while. */ default: break; }}?>
If - Switch<?php
$i = 1;if ($i == 0) { echo "i equals 0";} elseif ($i == 1) { echo "i equals 1";} elseif ($i == 2) { echo "i equals 2";}
switch ($i) { case 0: echo "i equals 0"; break; case 1: echo "i equals 1"; break; case 2: echo "i equals 2"; break;}?>
Do..While - IF
<?phpdo { if ($i < 5) { echo "i is not big enough"; break; } $i *= $factor; if ($i < $minimum_limit) { break; } echo "i is ok";
/* process i */
} while (0);?>