Programming PHP

if
The if statement checks the truthfulness of an expression and, if the expression is
true, evaluates a statement. An if statement looks like:
if (expression)
statement
To specify an alternative statement to execute when the expression is false, use the
else keyword:
if (expression)
statement
else
statement
For example:
if ($user_validated)
echo "Welcome!";
else
echo "Access Forbidden!";
To include more than one statement in an if statement, use a block—a curly braceenclosed
set of statements:
if ($user_validated) {
echo 'Welcome!";
$greeted = 1;
} else {
echo "Access Forbidden!";
exit;
}
PHP provides another syntax for blocks in tests and loops. Instead of enclosing the
block of statements in curly braces, end the if line with a colon (:) and use a specific
keyword to end the block (endif, in this case). For example:
if ($user_validated) :
echo "Welcome!";
$greeted = 1;
else :
echo "Access Forbidden!";
exit;
endif;
Other statements described in this chapter also have similar alternate style syntax
(and ending keywords); they can be useful if you have large blocks of HTML inside
your statements. For example:
First Name:Sophia
This is the Title of the Book, eMatter Edition
Copyright © 2002 O’Reilly & Associates, Inc. All rights reserved.
Flow-Control Statements | 47