Php-mysql Course

Recursive Functions are functions that auto-call themself. Generally, a recursive function returns a value that are passed as argument, so the value is passed from an auto-call to the other, until it is returned.
Recursive functions are very useful in equations with factorial numbers and some operatios with multi-dimensional array.
Factorials are written like 6! and this means: 6 * 5 * 4 * 3 * 2 * 1. So 6! is 4320 and 4! is 24.
In the fallowing example we have a recursive function that finds the factorial of a number "$nr" (here 8).

// this function auto-calls itself (decrementing $nr) until $nr is 0
function factorial($nr) {
 if($nr > 0) $re = $nr * factorial($nr-1);
 else if($nr == 0) $re = 1;

 return $re;

echo '8 factorial is: '. factorial(8); // 8 factorial is: 45360

- To see another example, visit this page: Get all the unique numbers from two-dimensional array.

Daily Test with Code Example

Which attribute is used in <img> tag for the address of the image?
href src rel
<img src="" width="191" height="63" alt="Courses-Web" />
Which CSS code hides the element on page?
display: none; display: inline; position: relative;
#id {
  display: none;
What instruction stops the execution of a while() or for() statement?
continue prompt() break
for(var i = 0; i< 8; i++) {
  if(i > 1) break;
Indicate the function that can create a constant.
define() include() defined()
define("CONSTANT_NAME", "value");
Recursive Functions in PHP

Last accessed pages

  1. Add, Change, and Remove Attributes with jQuery (46144)
  2. Align DIVs on the same line (8137)
  3. Brush and Eraser (3234)
  4. Read Excel file data in PHP - PhpExcelReader (96004)
  5. MD5 hash string in JavaScript (4641)

Popular pages this month

  1. Courses Web: PHP-MySQL JavaScript Node.js Ajax HTML CSS (443)
  2. SHA1 Encrypt data in JavaScript (234)
  3. Read Excel file data in PHP - PhpExcelReader (217)
  4. PHP Unzipper - Extract Zip, Rar Archives (217)
  5. Get and Modify content of an Iframe (139)