PHP8 - Create your own Functions

Language: PHP
function paint($color) {
    echo "The color of the room is " . $color;
}
 
paint("blue");

Language: PHP
function paint($color="red") {
    echo "The color of the room is " . $color;
}
 
paint();

Language: PHP
/*
*	Remove all the whitespaces
*/
 
$color = "blue";
function remove_whitespace($string) 
{
	$l = 0;
	$output = ';';;
	for ($i = 0, $n = strlen($string); $i < $n; $i++) 
	{
		  $num = substr($string, $i, 1);
		  if ($num == '; ';) 
		  {
				$l++;
		  } 
		  else 
		  {
				$output .= $num;
		  }
		  return $output;
	}
}
function paint($color="red") {
    echo "The color of the room is " . $color;
}
$color = remove_whitespace($color);
paint(color);

Language: PHP
$discount_total = $total_spent - ($total_spent * $discount);
$total_charged = $discount_total;

Language: PHP
$total_charged = $total_spent - ($total_spent * $discount);

Language: PHP
$discount_total = $total_spent * $discount;
$total_charged = $total_spent - $discount_total;

Language: PHP
function testNum() {
			$day = $_POST[';day';];
			$month = $_POST[';month';];
			$year = $_POST[';year';];
 
			if (is_int($day) && is_int($month) && is_int($year)) {
				testVal();
			}
 
			else {
				echo "Sorry please type in numbers";
			}
		}

Language: PHP
function testNum() { 
			if (is_int($day) && is_int($month) && is_int($year)) {
				testVal();
			}
 
			else {
 
echo "Sorry please type in numbers";
 
}
 
 
 
$day = $_POST[';day';];
$month = $_POST[';month';];
$year = $_POST[';year';];
 
testNum($day.... etc)

Language: PHP
<?php
		$day = "";
		$month = "";
		$year = "";
		$currentDate = getdate();
 
		function getAnswer() {
				$day = $_POST[';day';];
				$month = $_POST[';month';];
				$year = $_POST[';year';];
				$currentDate = getdate();
 
					if ($year == $currentDate[';year';]) {
						if ($month == $currentDate[';mon';]) {
							$dayAnswer = $currentDate[';mday';] - $day;
							$dayDate = abs($dayAnswer);
							echo "Posted " . $dayDate . " Days Ago";
					}
 
					else {
						$monthAnswer = $month - $currentDate[';mon';];
						$monthDate = abs($monthAnswer);
						echo "Posted " . $monthDate . " Months Ago";
					}
			}
			else {
				echo "Posted more than a year ago";
			}
		}
 
		function testVal() {
			$day = $_POST[';day';];
			$month = $_POST[';month';];
			$year = $_POST[';year';];
			$currentDate = getdate();
 
			if ($year > $currentDate[';year';]) {
				echo "invalid year, please try again";
			}
 
			elseif ($month > $currentDate[';mon';]) {
					echo "invalid month, please try again";
			}
			elseif ($day > $currentDate[';mday';]) {
						echo "invalid day, please try again";
			}
 
			else {
				getAnswer();
			}
		}
 
		function testNum() {
			$day = $_POST[';day';];
			$month = $_POST[';month';];
			$year = $_POST[';year';];
 
			if (is_int($day) && is_int($month) && is_int($year)) {
				testVal();
			}
 
			else {
				echo "Sorry please type in numbers";
			}
		}
 
		if (isset($_POST[';Submit1';])) {
			testNum();
		}
	?>
    <br />
    Date of last post:<br />
    <FORM NAME ="form1" METHOD ="POST" ACTION ="Dates.php">
    Day: <INPUT TYPE = "TEXT" VALUE ="<?php echo $day; ?>" name="day"> Month: <INPUT TYPE = "TEXT" VALUE ="<?php echo $month; ?>" name="month"> Year: <INPUT TYPE = "TEXT" VALUE ="<?php echo $year; ?>" name="year">
<INPUT TYPE = "Submit" Name = "Submit1" VALUE = "Submit">
    </FORM>

Quote

To test if a variable is a number or a numeric string (such as form input, which is always a string), you must use is_numeric().

Language: PHP
$day = $_POST[';day';];
$month = $_POST[';month';];
$year = $_POST[';year';];
 //then pass it to the function
testNum($day, $month, $year)

Quote

To test if a variable is a number or a
> numeric string (such as form input, which is
> always a string), you must use
> is_numeric().

Language: PHP
<?php
// function relies on arguments passed to it, not on potentially arbitrary external vars
function testDate($year_val, $month_val, $day_val){
    if( is_numeric($year_val) && is_numeric($month_val) && is_numeric($day_val) ){
    /* insert code */
   }
}
?>

Language: PHP
<?php
// values from the form submission
$year_value = $_POST[';year';];
$month_value = $_POST[';month';];
$day_value = $_POST[';day';];
 
//pass those values to the function
testDate($year_value, $month_value, $day_value);
?>

Language: HTML
<select name="year">
<option>--Choose a year---</option>
<option value="2012">2012</option>
<option value="2011">2011</option>
<option value="2010">2010</option>
...
</select>

Language: PHP
<?php
$page = $_GET[';page';];
       include(';includes/header.php';);
if($page==""){
include(';includes/home.php';);
} elseif ($page=="contact"){
include(';includes/contact.php';);
}
       include(';includes/footer.php';);
?>

Language: PHP
<?php
$page = $_GET[';page';];
$person = $_GET[';person';];
   include(';includes/header.php';);
if($page==""){
include(';includes/home.php';);
} elseif ($page=="contact"){
       include(';includes/contactheader.php';);
             if ($person=="john"){
             include(';includes/contacts/john.php';);
             }
       include(';includes/contactfooter.php';);
}
  include(';includes/footer.php';);
?>

Language: PHP
$newfunc = create_function(';$a,$b';, ';return "($a + $b)"';);
echo $newfunc(10, 20);