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PHP opening and closing Tags syntaxThere are four different pairs of opening and closing tags which can be used in php. Here is the list of tags.
Default Syntax The default syntax starts with "<? php" and ends with "?>". Example:
View the example (with default tag syntax) in the browser. Short open Tags The short tags starts with "<?" and ends with "?>". Short style tags are only available when they are enabled in php.ini configuration file on servers. Example:
Omit the PHP closing tag at the end of the file It is recommended that a closing PHP tag shall be omitted in a file containing only PHP code so that occurrences of accidental whitespace or new lines being added after the PHP closing tag, which may start output buffering causing uncalled for effects can be avoided. Example:
PHP Statement separation In PHP, statements are terminated by a semicolon (;) like C or Perl. The closing tag of a block of PHP code automatically implies a semicolon, there is no need to have a semicolon terminating the last line of a PHP block. Rules for statement separation
Valid Codes
In the above example, both semicolon(;) and a closing PHP tag are present.
In the above example, there is no semicolon(;) after the last
instruction but a closing PHP tag is present. <?php echo 'Here the last closing tag is omitted' ; In the above example, there is a semicolon(;) in the last instruction but there is no closing PHP tag. PHP Case sensitivity In PHP the user defined functions, classes, core language keywords (for example if, else, while, echo etc.) are case-insensitive. Therefore the three echo statements in the following example are equal. Example - 1
Output: We are learning PHP case sensitivity We are learning PHP case sensitivity We are learning PHP case sensitivity View the example in the browser On the other hand, all variables are case-sensitive. Consider the following example. Only the first statement display the value as $amount because $amount, $AMOUNT, $amoUNT are three different variables. Example - 2
Output: The Amount is : 200 The Amount is : The Amount is : View the example in the browser PHP whitespace insensitivity In general, whitespace is not visible on the screen, including spaces, tabs, and end-of-line characters i.e. carriage returns. In PHP whitespace doesn't matter in coding. You can break a single line statement to any number of lines or number of separate statements together on a single line. The following two examples are same : Example:
Output: The Name of student is : David Rayy His Class is : V and Roll No. is 12 View the example in the browser Example: Advance whitespace insensitivity
Output: The Name of student is : David Rayy His Class is : V and Roll No. is 12 View the example in the browser Example : Whitespace insensitivity with tabs and spaces In the following example spaces and tabs are used in a numeric operation, but in both cases, $xyz returns the same value.
Output: 23 23 View the example in the browser PHP: Single line and Multiple lines Comments Single line comment PHP supports the following two different way of commenting. # This is a single line comment. //This is another way of single line comment. Example:
Output: How to make single line comment. View the example in the browser Multiple lines comments PHP supports 'C', style comments. A comment starts with the character pair /* and terminates with the character pair */. /* This is a multiple comment testing, Example:
Output: How to make multiline comments View the example in the browser Multiple lines comments can not be nested
First PHP Script Here is the first PHP script which will display "Hello World..." in the web browser.
The tags tell the web server to treat everything inside the tags as PHP code to run. The code is very simple. It uses an in-build PHP function "echo" to display the text "Hello World ..." in the web page. Everything outside these tags is sent directly to the browser. Pictorial presentation Combining PHP and HTML PHP syntax is applicable only within PHP tags. PHP can be embedded in HTML and placed anywhere in the document. When PHP is embedded in HTML documents and PHP parses this document it interpreted the section enclosed with an opening tag (<?php) and closing tag (?>) of PHP and ignore the rest parts of the document. PHP and HTML are seen together in the following example.
Practice here online : Previous: Install WAMP Do I need to closeTo recap, closing PHP tags (?>) are entirely optional if you're coding a PHP-only file and there's no intermingled HTML. Files containing single class definitions are good candidates. Omitting the closing tag has another benefit: it becomes impossible to accidentally add white space to the end of the file.
How do I start and end a PHP file?User Contributed Notes 1 note
If you want your file to be interpreted as php then your file must start and end with <? php and ?> and everything outside of that is ignored by the php parser.
How do you escape HTML tags in PHP?The strip_tags() function strips a string from HTML, XML, and PHP tags. Note: HTML comments are always stripped. This cannot be changed with the allow parameter. Note: This function is binary-safe.
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