Basic PHP Syntax
A PHP script always starts with <?php and ends with ?>. A PHP script can be placed anywhere in the document.
A PHP file must have a .php extension.
<html>
<body>
<?php
echo "Hello World";
//This is a comment
/*
This is
a comment
block
*/
?>
</body>
</html>
PHP Variables
<?php
$txt="Hello World!";
$x=16;
echo $x;
echo $txt;
?>
PHP Variables
PHP has four different variable scopes:
- local
- global
- static
- parameter
$a = 5;
$b = 10;
function myTest()
{
global $a, $b; output=15
$b = $a + $b;
}
myTest();
echo $b;
?>
PHP If...Else Statement
<html>
<body>
<?php
$d=date("D");
if ($d=="Fri")
{
echo "Have a nice weekend!";
}
elseif ($d=="Sun")
{
echo "Have a nice Sunday!";
}
else
{
echo "Have a nice day!";
}
?>
</body>
</html>
PHP Switch Statement
<html>
<body>
<?php
$x=1;
switch ($x)
{
case 1:
echo "Number 1";
break;
case 2:
echo "Number 2";
break;
case 3:
echo "Number 3";
break;
default:
echo "No number between 1 and 3";
}
?>
</body>
</html>
PHP Arrays
<?php
$cars[0]="Saab";
$cars[1]="Volvo";
$cars[2]="BMW";
$cars[3]="Toyota";
echo $cars[0] . " and " . $cars[1] . " are Swedish cars.";
?>
PHP While Loop
<html>
<body>
<?php
$i=1;
while($i<=5)
{
echo "The number is " . $i . "<br />"; output:The number is 1,
2,3,4,5
$i++;
}
?>
</body>
</html>
PHP do..While Loop
<html>
<body>
output:The number is 2
3,4,5,6.
<?php
$i=1;
do
{
$i++;
echo "The number is " . $i . "<br />";
}
while ($i<=5);
?>
</body>
</html>
PHP For Loop
<html>
<body>
<?php
for ($i=1; $i<=5; $i++)
{
echo "The number is " . $i . "<br />";
}
?>
</body>
</html>
PHP For each Loop
<html>
<body>
<?php
$x=array("one","two","three");
foreach ($x as $value)
{
echo $value . "<br />";
}
?>
</body>
</html>
Output:one
two
three
two
three
PHP Functions
1)<html>
<body>
<?php
function writeName($fname)
{
echo $fname . " Refsnes.<br />";
}
echo "My name is ";
writeName("Kai Jim");
echo "My sister's name is ";
writeName("Hege");
echo "My brother's name is ";
writeName("Stale");
?>
</body>
</html>
<body>
<?php
function writeName($fname)
{
echo $fname . " Refsnes.<br />";
}
echo "My name is ";
writeName("Kai Jim");
echo "My sister's name is ";
writeName("Hege");
echo "My brother's name is ";
writeName("Stale");
?>
</body>
</html>
output:
My name is Kai Jim Refsnes.
My sister's name is Hege Refsnes.
My brother's name is Stale Refsnes.
2)<html>
<body>
<?php
function add($x,$y)
{
$total=$x+$y;
return $total;
}
echo "1 + 16 = " . add(1,16);
?>
</body>
</html>
output:1 + 16 = 17
PHP Form Handling
index.php
<html>
<body>
<form action="welcome.php" method="post">
Name: <input type="text" name="fname" />
Age: <input type="text" name="age" />
<input type="submit" />
</form>
</body>
</html>
<body>
<form action="welcome.php" method="post">
Name: <input type="text" name="fname" />
Age: <input type="text" name="age" />
<input type="submit" />
</form>
</body>
</html>
welcome.php
<html>
<body>
Welcome <?php echo $_POST["fname"]; ?>!<br />
You are <?php echo $_POST["age"]; ?> years old.
</body>
</html>
<body>
Welcome <?php echo $_POST["fname"]; ?>!<br />
You are <?php echo $_POST["age"]; ?> years old.
</body>
</html>
Output:
Welcome Asanhussain!
You are 22 years old.
You are 22 years old.
PHP GET Function
The predefined $_GET variable is used to collect values in a form with method="get".
Information sent from a form with the GET method is visible to everyone (it will be displayed in the browser's address bar) and has limits on the amount of information to send.
index.php
<html>
<body>
<form action="welcome.php" method="post">
Name: <input type="text" name="fname" />
Age: <input type="text" name="age" />
<input type="submit" />
</form>
</body>
</html>
<body>
<form action="welcome.php" method="post">
Name: <input type="text" name="fname" />
Age: <input type="text" name="age" />
<input type="submit" />
</form>
</body>
</html>
http://localhost/hussain/welcome.php?fname=Peter&age=37
The "welcome.php" file can now use the $_GET variable to collect form data (the names of the form fields will automatically be the keys in the $_GET array):
welcome.php
<html>
<body>
Welcome <?php echo $_GET["fname"]; ?>!<br />
You are <?php echo $_GET["age"]; ?> years old.
</body>
</html>
<body>
Welcome <?php echo $_GET["fname"]; ?>!<br />
You are <?php echo $_GET["age"]; ?> years old.
</body>
</html>
Note: 1)This method should not be used when sending passwords or other sensitive information!
2)The get method is not suitable for very large variable values.
It should not be used with values exceeding 2000 characters.
PHP POST Function
The predefined $_POST variable is used to collect values from a form sent with method="post".
Information sent from a form with the POST method is invisible to others and has no limits on the amount of information to send.
However, because the variables are not displayed in the URL, it is not possible to bookmark the page.
PHP REQUEST Function
The predefined $_REQUEST variable contains the contents of both $_GET, $_POST, and $_COOKIE.
The $_REQUEST variable can be used to collect form data sent with both the GET and POST methods.
Welcome <?php echo $_REQUEST["fname"]; ?>!<br />
You are <?php echo $_REQUEST["age"]; ?> years old.
You are <?php echo $_REQUEST["age"]; ?> years old.
No comments:
Post a Comment