is_null(3) [php man page]

IS_NULL(3)								 1								IS_NULL(3)

is_null - Finds whether a variable is NULL

SYNOPSIS

       bool is_null (mixed  $var)

DESCRIPTION

	Finds whether the given variable is NULL.

PARAMETERS

	      o $var
		- The variable being evaluated.

RETURN VALUES

	Returns TRUE if $var is null, FALSE otherwise.

EXAMPLES

       Example #1

	      is_null(3) example

	      <?php

	      error_reporting(E_ALL);

	      $foo = NULL;
	      var_dump(is_null($inexistent), is_null($foo));

	      ?>

	      Notice: Undefined variable: inexistent in ...
	      bool(true)
	      bool(true)

SEE ALSO

       The NULL type, isset(3), is_bool(3), is_numeric(3), is_float(3), is_int(3), is_string(3), is_object(3), is_array(3).

PHP Documentation Group 														IS_NULL(3)

IS_INT(3)								 1								 IS_INT(3)

is_int - Find whether the type of a variable is integer

SYNOPSIS

       bool is_int (mixed  $var)

DESCRIPTION

	Finds whether the type of the given variable is integer.

       Note

	       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(3).

PARAMETERS

	      o $var
		- The variable being evaluated.

RETURN VALUES

	Returns TRUE if $var is an integer, FALSE otherwise.

EXAMPLES

       Example #1

	      is_int(3) example

	      <?php
	      $values = array(23, "23", 23.5, "23.5", null, true, false);
	      foreach ($values as $value) {
		  echo "is_int(";
		  var_export($value);
		  echo ") = ";
		  var_dump(is_int($value));
	      }
	      ?>

	      The above example will output:

	      is_int(23) = bool(true)
	      is_int('23') = bool(false)
	      is_int(23.5) = bool(false)
	      is_int('23.5') = bool(false)
	      is_int(NULL) = bool(false)
	      is_int(true) = bool(false)
	      is_int(false) = bool(false)

SEE ALSO

       is_bool(3), is_float(3), is_numeric(3), is_string(3), is_array(3), is_object(3).

PHP Documentation Group 														 IS_INT(3)