php man page for splfixedarray

SPLFIXEDARRAY(3)							 1							  SPLFIXEDARRAY(3)

The SplFixedArray class

INTRODUCTION
	The SplFixedArray class provides the main functionalities of array. The main differences between a SplFixedArray and a normal PHP array is
       that the SplFixedArray is of fixed length and allows only integers within the range as indexes. The advantage is that it  allows  a  faster
       array implementation.

CLASS SYNOPSIS
       SplFixedArray

       SplFixedArrayIteratorArrayAccessCountable

       Methods

       o public SplFixedArray::__construct ([int  $size])

       o public int SplFixedArray::count (void	)

       o public mixed SplFixedArray::current (void  )

       o publicstatic SplFixedArray SplFixedArray::fromArray (array  $array, [bool  $save_indexes = true])

       o public int SplFixedArray::getSize (void  )

       o public int SplFixedArray::key (void  )

       o public void SplFixedArray::next (void	)

       o public bool SplFixedArray::offsetExists (int  $index)

       o public mixed SplFixedArray::offsetGet (int  $index)

       o public void SplFixedArray::offsetSet (int  $index, mixed  $newval)

       o public void SplFixedArray::offsetUnset (int  $index)

       o public void SplFixedArray::rewind (void  )

       o public int SplFixedArray::setSize (int  $size)

       o public array SplFixedArray::toArray (void  )

       o public bool SplFixedArray::valid (void  )

       o public void SplFixedArray::__wakeup (void  )

EXAMPLES
       Example #1

	      SplFixedArray usage example

	      <?php
	      // Initialize the array with a fixed length
	      $array = new SplFixedArray(5);

	      $array[1] = 2;
	      $array[4] = "foo";

	      var_dump($array[0]); // NULL
	      var_dump($array[1]); // int(2)

	      var_dump($array["4"]); // string(3) "foo"

	      // Increase the size of the array to 10
	      $array->setSize(10);

	      $array[9] = "asdf";

	      // Shrink the array to a size of 2
	      $array->setSize(2);

	      // The following lines throw a RuntimeException: Index invalid or out of range
	      try {
		  var_dump($array["non-numeric"]);
	      } catch(RuntimeException $re) {
		  echo "RuntimeException: ".$re->getMessage()."
";
	      }

	      try {
		  var_dump($array[-1]);
	      } catch(RuntimeException $re) {
		  echo "RuntimeException: ".$re->getMessage()."
";
	      }

	      try {
		  var_dump($array[5]);
	      } catch(RuntimeException $re) {
		  echo "RuntimeException: ".$re->getMessage()."
";
	      }
	      ?>

	      The above example will output:

	      NULL
	      int(2)
	      string(3) "foo"
	      RuntimeException: Index invalid or out of range
	      RuntimeException: Index invalid or out of range
	      RuntimeException: Index invalid or out of range

PHP Documentation Group 													  SPLFIXEDARRAY(3)