PHP, Structures and Functions, Fundamental Syntaxes

for

Full code fragment that performs REPEATED ACTIONS until a desired result is reached.

Performs ITERATION of a variable executed in THREE PARAMETERIZED PHASES:

    1 . Assigning an INITIAL VALUE to the variable.

    2 . Establishment of the ITERATIVE CALCULATION that will be submitted to the variable.

    3 . Completion of the ITERATIVE calculation.

Behavior for loops are the most complex loops in PHP.

This function works as its analog in C language.

FIRST SYNTAX TYPE

In the following, we will show the FIRST SYNTAX TYPE of - for - conditional structure:


<?php

// STRUCTURE #1

for ( expr1; expr2; expr3)
    statement


where,

expr1 = first expression to be evaluated once unconditionally 
             at the beginning of the loop
             
expr2 = second expression, related to expr1

expr3 = third expression - the end of each iteration

?>

SECOND SYNTAX TYPE

In the following, we will show the SECOND SYNTAX TYPE of - for - conditional structure:


<?php 

// STRUCTURE #2 

for ( expr1; expr2; expr3) 
{ 
    statement 
} 


where, 

expr1 = first expression to be evaluated once unconditionally 
             at the beginning of the loop 
              
expr2 = second expression, related to expr1 

expr3 = third expression - the end of each iteration 

?>

EXERCISE


<?php

for ($n01 = 0; $n01 <= 9; $n01++)
echo $n01 . '&nbsp;&nbsp;';

?>

RESULT

0 1 2 3 4 5 6 7 8 9

EXERCISE


<?php

for ($n02 = 9; $n02 >= 0; $n02--)
{
echo $n02 . '&nbsp;&nbsp;';
}

?>

RESULT

9 8 7 6 5 4 3 2 1 0

EXERCISE


<?php

$a03 = array('Sunday', 
                     'Monday', 'Tuesday', 'Wednesday', 
                     'Thursday', 'Friday', 
                     'Saturday');

for ($n03 = 0; $n03 <= (count($a03) - 1); $n03++)
{
echo $a03[$n03] . '<br>';
}

?>