Tag: snippet

I’ll just cut to the chase.

/**
 * create an array of all dates between two specified dates
 * @param datetime $strDateFrom
 * @param datetime $strDateTo
 * @return array
 */
function createDateRangeArray($strDateFrom, $strDateTo) {		
	$aryRange = array();
	$iDateFrom = mktime(1, 0, 0, substr($strDateFrom, 5, 2), substr($strDateFrom, 8, 2), substr($strDateFrom, 0, 4));
	$iDateTo = mktime(1, 0, 0, substr($strDateTo, 5, 2), substr($strDateTo, 8, 2), substr($strDateTo, 0, 4));
	if ($iDateTo >= $iDateFrom) {
		array_push($aryRange, date("Y-m-d", $iDateFrom));			
		while ($iDateFrom < $iDateTo) {
			$iDateFrom = $iDateFrom + 86400;
			array_push($aryRange, date("Y-m-d", $iDateFrom));
		}
	}
	return $aryRange;
}

If your users link to some URL, it’s always nice to check if their input actually represents a valid URL. You can do just that with this function:

/**
 * return true if the passed variable is a valid URL address
 * @param $url
 * @return boolean
 */
function isValidURL($url) {
	$pattern  = '/^(([\w]+:)?\/\/)?(([\d\w]|%[a-fA-f\d]{2,2})+(:([\d\w]|%[a-fA-f\d]{2,2})+)?@)?([\d\w][-\d\w]{0,253}[\d\w]\.)+[\w]{2,4}(:[\d]+)?(\/([-+_~.\d\w]|%[a-fA-f\d]{2,2})*)*(\?(&?([-+_~.\d\w]|%[a-fA-f\d]{2,2})=?)*)?(#([-+_~.\d\w]|%[a-fA-f\d]{2,2})*)?$/';
	return preg_match($pattern, $url);
}

If this function returns true, you might want to actually open the URL (using file_get_contents() or some other function) to see if it works.

It can be tricky to really understand the value of 7312946 or 983217 at the first glance. Saying 7.3M and 983k seems like a much better option. How to convert numbers into a nicer format? Like this:

/**
 * create a nicely formatted number
 * @param $number a large number
 * @param $shorten default true = append k or M, false = format with commas and dots
 * @return int
 */
function createHumanReadableInteger($number, $shorten = true) {
	if (is_numeric($number)) {
		if ($shorten) {
			if ($number < 100000) {
				$return_int = number_format($number, 0);
			} else {
				$number_proc = $number;
				$units = explode(" ", "B k M G T P");
				for ($i = 0; $number_proc > 1000; $i++) {
					$number_proc = $number_proc / 1000;
				}
				if ($number > 1000000) {
					$return_int = round($number_proc, 2) . " " . $units[$i];
				} else {
					$return_int = round($number_proc, 1) . " " . $units[$i];	
				}
			}
		} else {
			$return_int = number_format($number, 0);
		}
		return $return_int;	
	} else {
		return 0;
	}
}

Here’s how:

/**
 * convert a datetime value (Y-m-d H:i:s) to UNIX timestamp value
 * @param datetime $datetime
 * @return timestamp
 */
function datetime_to_timestamp($datetime) {
    list($date, $time) = explode(" ", $datetime);
    list($year, $month, $day) = explode("-", $date);
    list($hour, $minute, $second) = explode(":", $time);
    return mktime($hour, $minute, $second, $month, $day, $year);
}

It’s a bit tricky to sort multidimensional arrays in PHP by one of array’s subkeys, but it can absolutely be done. Check it out:

/**
 * USING POINTER TO ARRAY - sort an array of arrays with associative indeces by one of those associative values
 * @param $array pointer to our array
 * @param $subkey associative index that we want to order by
 * @param $sort_type [SORT_ASC|SORT_DESC]
 * @return void
 */
function sortBySubkey(&$array, $subkey, $sort_type = SORT_ASC) {
   foreach ($array as $subarray) {
      $keys[] = $subarray[$subkey];
   }
   array_multisort($keys, $sort_type, $array);
}

Sometimes you are given a string (someone’s name, or some title, or something completely different) and you cannot afford to use this string if you’re not completely sure what to expect. For instance, sometimes you need to convert a string into something that consists only of alphanumerical characters and spaces. You can always use the following function:

/**
 * create a string that only consists of alphanumerical characters and spaces
 * @param $string
 * @return string
 */
function createSafeString($string) {
	$string = strtolower($string);
        $output = "";
	for ($i = 0; $i < strlen($string); $i++) {
		$ord = ord($string[$i]);
		if (($ord >= 48 && $ord <= 57) || ($ord >= 65 && $ord <= 90) || ($ord >= 97 && $ord <= 122) || ($ord == 32)) {
			$output .= $string[$i];
		}
	}
	return $string;
}