Say you are studying for an exam.
If you study hard you will pass the exam
Else you will fail
How does this translate into something useful for PHP developers? Well
consider this:
If--Else Example
Here is an
"if--else" statement in PHP.
PHP Code:
$number = 4;
if( $number == 4 ) {
echo "The if statement evaluated to true";
} else {
echo "The if statement evaluated to false";}
Display:
The if statement evaluated to true
Let us step through the code, line by line.
- First a PHP variable called "$number" was
set to "4"
- Next we compare to see if "$number" was equal
to "4". To do such a comparison we use "==".
- As "$number" is indeed Equal To "4", condition
evaluated is true.
- Therefore, "The if statement evaluated to true" is echoed.
Execute Else Code with False
On the other hand, if the if statement was false, then the code
contained in the else segment would have been executed.
Here is what
would happen if we changed to "$number" to anything but "4".
PHP Code:
$number = 421;
if ( $number == 4 ) {
echo "The if statement evaluated to true";
} else {
echo "The if statement evaluated to false";
}
Display:
The if statement evaluated to false
The variable was set to "421", which is not equal to "4" and the if statement
was false.
The code segment contained within the else
was used in this case.
Note
For more detail please see
Php Manual at http://www.php.net