php man page for array_merge

ARRAY_MERGE(3)								 1							    ARRAY_MERGE(3)

array_merge - Merge one or more arrays

SYNOPSIS
       array array_merge (array  $array1, [array  $...])

DESCRIPTION
	Merges	the  elements of one or more arrays together so that the values of one are appended to the end of the previous one. It returns the
       resulting array.

	If the input arrays have the same string keys, then the later value for that key will overwrite the previous one. If, however, the  arrays
       contain numeric keys, the later value will not overwrite the original value, but will be appended.

	Values in the input array with numeric keys will be renumbered with incrementing keys starting from zero in the result array.

PARAMETERS
	      o $array1
		- Initial array to merge.

	      o $...
		- Variable list of arrays to merge.

RETURN VALUES
	Returns the resulting array.

EXAMPLES
       Example #1

	      array_merge(3) example

	      <?php
	      $array1 = array("color" => "red", 2, 4);
	      $array2 = array("a", "b", "color" => "green", "shape" => "trapezoid", 4);
	      $result = array_merge($array1, $array2);
	      print_r($result);
	      ?>

	      The above example will output:

	      Array
	      (
		  [color] => green
		  [0] => 2
		  [1] => 4
		  [2] => a
		  [3] => b
		  [shape] => trapezoid
		  [4] => 4
	      )

       Example #2

	      Simple array_merge(3) example

	      <?php
	      $array1 = array();
	      $array2 = array(1 => "data");
	      $result = array_merge($array1, $array2);
	      ?>

	       Don't forget that numeric keys will be renumbered!

	      Array
	      (
		  [0] => data
	      )

	       If  you	want  to  append array elements from the second array to the first array while not overwriting the elements from the first
	      array and not re-indexing, use the + array union operator:

	      <?php
	      $array1 = array(0 => 'zero_a', 2 => 'two_a', 3 => 'three_a');
	      $array2 = array(1 => 'one_b', 3 => 'three_b', 4 => 'four_b');
	      $result = $array1 + $array2;
	      var_dump($result);
	      ?>

	       The keys from the first array will be preserved. If an array key exists in both arrays, then the element from the first array  will
	      be used and the matching key's element from the second array will be ignored.

	      array(5) {
		[0]=>
		string(6) "zero_a"
		[2]=>
		string(5) "two_a"
		[3]=>
		string(7) "three_a"
		[1]=>
		string(5) "one_b"
		[4]=>
		string(6) "four_b"
	      }

       Example #3

	      array_merge(3) with non-array types

	      <?php
	      $beginning = 'foo';
	      $end = array(1 => 'bar');
	      $result = array_merge((array)$beginning, (array)$end);
	      print_r($result);
	      ?>

	      The above example will output:

	      Array
		  (
		      [0] => foo
		      [1] => bar
		  )

SEE ALSO
       array_merge_recursive(3), array_replace(3), array_combine(3), array operators.

PHP Documentation Group 													    ARRAY_MERGE(3)