Add a PDO iterator object.

Author: lincanbin

src/PDO.Iterator.class.php

@@ -0,0 +1,39 @@
+<?php
+class PDOIterator implements Iterator {
+    private $position = 0;
+    private $pdo;
+    private $fetchMode;
+    private $nextResult;
+
+    public function __construct(PDOStatement $pdo, $fetchMode = PDO::FETCH_ASSOC) {
+        $this->position = 0;
+        $this->pdo = $pdo;
+        $this->fetchMode = $fetchMode;
+    }
+
+    function rewind() {
+        $this->position = 0;
+        $this->pdo->execute();
+    }
+
+    function current() {
+        return $this->nextResult;
+    }
+
+    function key() {
+        return $this->position;
+    }
+
+    function next() {
+        ++$this->position;
+        $this->nextResult = $this->pdo->fetch($this->fetchMode, PDO::FETCH_ORI_NEXT);
+    }
+
+    function valid() {
+        $invalid = $this->nextResult === false;
+        if ($invalid) {
+            $this->pdo->closeCursor();
+        }
+        return !$invalid;
+    }
+}