php_training_day3_string_operators

<?php
/*
.   concatenate     Combine $x & $y
.=  concatenate assignment  append $x & y

$x = 'Test';
$y = 'Test 2';
echo $x .= ' Test 3';

// echo $x . ' ' . $y;
$header = 'CC: [email protected]';
$header .= 'BCC: [email protected]';
echo $header;
*/

/*
ARRAY OPERATORS
To compare arrays

+       Union           $x + $y     Union of $x and $y
==      Equality        $x == $y    Returns true if $x & $y have same key/value pairs.
===     Identity        $x === $y   Returns true if $x & $y have the same key/value pairs in same order and same type
!=      Inequality      $x != $y    Returns true if $x is not equal to $y
<>      Inequality      $x <> $y    Returns true if $x is not equal to $y
!==     Not Identity    $x !== $y     Returns true if $x is not identical to $y

$x = array('a' => 'red', 'b' => 'green');
$y = array('c' => 'blue', 'd' => 'orange');

var_dump($x !== $y);

CONSTANTS
define('COUNTRY_NAME', 'Nepal');
echo COUNTRY_NAME;

CONDITIONAL STATEMENTS
1. If Statement
if (condition) {
    code block
}

2. If Else
    if (condition) {
      this code block runs
    } else {
        this code block runs
    }

3. If Else-If Statement
    if (condition) {
        code
    } elseif (condition) {
        code
    } elseif (condition) {
        code
    } else {
        code
    }

$result = 80;
if ($result = 70) {
    echo 'Grade A';
} elseif ($result >= 60) {
    echo 'Grade B';
} else {
    echo 'Pass';
}

TERNARY OPERATORS
one line if else
$var = 1;
$var_is_greater_than_two = ($var > 2 ? true : false);
var_dump($var_is_greater_than_two);

SWITCH STATEMENTS
*/
$num = 'Test Number';
switch ($num) {
    case 'Test Number':
        echo 'One';
        break;
    case 2:
        echo 'Two';
        break;
    case 3:
        echo 'Three';
        break;
    default:
        echo 'No Number';
}