php mysql training : module 3
DESCRIPTION
PHP HTML Embedding Tags and Syntax Simple PHP Script Example PHP and HTTP Environment VariablesTRANSCRIPT
Agenda
● PHP HTML Embedding Tags and Syntax● Simple PHP Script Example● PHP and HTTP Environment Variables
PHP HTML Embedding Tags and Syntax
● HTML is written as <tag>content<tag>● Similarly, PHP Tags can be written as:
<?php method; ?>e.g. <?php echo ”Hello World!”; ?>
● So how does it makes sense?- Use different methods to generate contents dynamically- Call PHP functions and get results at run-time
Some other ways to achieve the same
● SGML Style (we have already seen!)<?php echo ”Hello World!”; ?>
● ASP / JSP Style<% echo “Hello World!”; %>OR (Shortcut)<p><?=”Hello World!”; ?>
● (Java)Script Style<script language = “php”>echo “Hello World!”;</script>
Simple PHP Script Example
● A sample program that illustrates different ways to code PHP!<html><head><title><? Echo “This is a sample PHP page!”; ?></title></head><body><h2>A math example</h2><p>10 + 11 = <%= 10+11 %><br/>and 8 + 9 = <% echo(8+9); %></body></html>
PHP and HTTP Environment Variables
● HTTP as a protocol is different, in PHP it has rich set of Global / environment variables.
● They are accessible globally!● $HTTP_GET_VARS or $_GET● $HTTP_POST_VARS or $_POST● $HTTP_COOKIE_VARS or $_COOKIE● $HTTP_SERVER_VARS or $_SERVER● $HTTP_ENV_VARS or $_ENV● $HTTP_POST_FILES
PHP and HTTP Environment Variables - 1
● $HTTP_GET_VARS&$HTTP_POST_VARS● Mostly used in GET and POST requests
respectively.● Contains request information / data.● Useful in form processing.
PHP and HTTP Environment Variables - 2
● $HTTP_COOKIE_VARS● Cookie is a very small, temporary text file● A way of session management● Stored and retrieved user specific information on
client
PHP and HTTP Environment Variables - 3
● $HTTP_SERVER_VARS● Various information about server● Examples:
SERVER_SOFTWARE “wamp”SERVER_NAME “www.sachinism.com”SERVER_PROTOCOL “HTTP/1.1”SERVER_PORT “80”REQUEST_METHOD “POST”QUERY_STRING “nm=hussu+age=32”REMOTE_HOST “hostname_machine”REMOTE_ADDR “192.168.10.1”AUTH_TYPE “basic”CONTENT_TYPE “x-url-encoded”
PHP and HTTP Environment Variables - 4
● $HTTP_ENV_VARS● Related to accessing machine and OS specific
environment variables● $HTTP_POST_FILES
● Related to file upload
Summary
● PHP can be written in either of 3 ways, SGML, Script or ASP / JSP styles.
● PHP environment variables like $_GET, $_POST, $_COOKIE, $_SERVER provides access to data stored in different ways like sent as request, stored as cookies, or some data about server.
Whats next?
● Learning language in dept...● Variables, Constants and Data Types, and Op-
erators● Decision Making, Flow Control and Loops