- MFH: Add new example

Author: helly25

ext/spl/examples/callbackfilteriterator.inc

@@ -0,0 +1,122 @@
+<?php
+
+/** @file callbackfilteriterator.inc
+ * @ingroup Examples
+ * @brief class CallbackFilterIterator
+ * @author  Marcus Boerger
+ * @author  Kevin McArthur
+ * @date    2006 - 2006
+ *
+ * SPL - Standard PHP Library
+ */
+
+/** @ingroup Examples
+ * @brief   A non abstract FiletrIterator that uses a callback foreach element
+ * @author  Marcus Boerger
+ * @author  Kevin McArthur
+ * @version 1.0
+ */
+class CallbackFilterIterator extends FilterIterator
+{
+	const USE_FALSE = 0;  /**< mode: accept no elements, no callback */
+	const USE_TRUE  = 1;  /**< mode: accept all elements, no callback */
+	const USE_VALUE = 2;  /**< mode: pass value to callback */
+	const USE_KEY   = 3;  /**< mode: pass key to callback */
+	const USE_BOTH  = 4;  /**< mode: pass value and key to callback */
+
+	const REPLACE   = 0x00000001; /**< flag: pass key/value by reference */
+
+	private $callback; /**< callback to use */
+	private $mode;     /**< mode any of USE_VALUE, USE_KEY, USE_BOTH */
+	private $flags;    /**< flags */
+	private $key;      /**< key value */
+	private $current;  /**< current value */
+
+	/** Construct a CallbackFilterIterator
+	 *
+	 * @param it        inner iterator (iterator to filter)
+	 * @param callback  callback function
+	 * @param mode      @copy $mode
+	 * @param flags     @copy $flags
+	 */
+	public function __construct(Iterator $it, $callback, $mode = self::USE_VALUE, $flags = 0)
+	{
+		parent::__construct($it);
+		$this->callback = $callback;
+		$this->mode     = $mode;
+		$this->flags    = $flags;
+	}
+
+	/** Call the filter callback
+	 * @return result of filter callback
+	 */
+	public function accept()
+	{
+		$this->key     = parent::key();
+		$this->current = parent::current();
+
+		switch($this->mode) {
+		default:
+		case self::USE_FALSE;
+			return false;
+		case self::USE_TRUE:
+			return true;
+		case self::USE_VALUE:
+			if($this->flags & self::REPLACE) {
+				return (bool) call_user_func($this->callback, &$this->current);
+			} else {
+				return (bool) call_user_func($this->callback, $this->current);
+			}
+		case self::USE_KEY:
+			if($this->flags & self::REPLACE) {
+				return (bool) call_user_func($this->callback, &$this->key);
+			} else {
+				return (bool) call_user_func($this->callback, $this->key);
+			}
+		case SELF::USE_BOTH:
+			if($this->flags & self::REPLACE) {
+				return (bool) call_user_func($this->callback, &$this->key, &$this->current);
+			} else {
+				return (bool) call_user_func($this->callback, $this->key, $this->current);
+			}
+		}
+	}
+
+	/** @return @copy $key */
+	function key()
+	{
+		return $this->key;
+	}
+
+	/** @return @copy $current */
+	function current()
+	{
+		return $this->current;
+	}
+
+	/** @return @copy $mode */
+	function getMode()
+	{
+		return $this->mode;
+	}
+
+	/** @param $mode set new mode, @see $mode */
+	function setMode($mode)
+	{
+		$this->mode = $mode;
+	}
+
+	/** @return @copy $flags */
+	function getFlags()
+	{
+		return $this->flags;
+	}
+
+	/** @param $flags set new flags, @see @copy $flags */
+	function setFlags($flags)
+	{
+		$this->flags = $flags;
+	}
+}
+
+?>