php man page for is_string

IS_STRING(3)								 1							      IS_STRING(3)

is_string - Find whether the type of a variable is string

SYNOPSIS
       bool is_string (mixed  $var)

DESCRIPTION
	Finds whether the type given variable is string.

PARAMETERS
	      o $var
		- The variable being evaluated.

RETURN VALUES
	Returns TRUE if $var is of type string, FALSE otherwise.

EXAMPLES
       Example #1

	      is_string(3) example

	      <?php
	      $values = array(false, true, null, 'abc', '23', 23, '23.5', 23.5, '', ' ', '0', 0);
	      foreach ($values as $value) {
		  echo "is_string(";
		  var_export($value);
		  echo ") = ";
		  echo var_dump(is_string($value));
	      }
	      ?>

	      The above example will output:

	      is_string(false) = bool(false)
	      is_string(true) = bool(false)
	      is_string(NULL) = bool(false)
	      is_string('abc') = bool(true)
	      is_string('23') = bool(true)
	      is_string(23) = bool(false)
	      is_string('23.5') = bool(true)
	      is_string(23.5) = bool(false)
	      is_string('') = bool(true)
	      is_string(' ') = bool(true)
	      is_string('0') = bool(true)
	      is_string(0) = bool(false)

SEE ALSO
       is_float(3), is_int(3), is_bool(3), is_object(3), is_array(3).

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