diff --git a/tasks/oop/classes/.htaccess b/tasks/oop/classes/.htaccess
new file mode 100644
index 0000000..872a3ce
--- /dev/null
+++ b/tasks/oop/classes/.htaccess
@@ -0,0 +1,3 @@
+Order deny,allow
+Deny from all
+Allow from 127.0.0.1
\ No newline at end of file
diff --git a/tasks/oop/classes/fieldValidator/fieldValidator.php b/tasks/oop/classes/fieldValidator/fieldValidator.php
new file mode 100644
index 0000000..ecdb1f6
--- /dev/null
+++ b/tasks/oop/classes/fieldValidator/fieldValidator.php
@@ -0,0 +1,112 @@
+<?php
+class FieldValidator
+{
+  /*
+  * Private members
+  */
+
+  private string $name;
+  private string $value;
+  private string $type;
+  private bool $required;
+  private int $minLen;
+  private int $maxLen;
+  private string $error;
+
+  /*
+  * Constructor
+  */
+
+  public function __construct(string $name, string $value, string $type, bool $required = false, int $minLen = -1, int $maxLen = -1, string $error = "")
+  {
+    $this->name = $name;
+    $this->value = $value;
+    $this->type = $type;
+    $this->required = $required;
+    $this->minLen = $minLen;
+    $this->maxLen = $maxLen;
+    $this->error = $error;
+
+    return $this;
+  }
+
+  /*
+  * Fluent Style
+  */
+
+  public static function create(string $name, string $value, string $type)
+  {
+    return new FieldValidator($name, $value, $type);
+  }
+
+  public function isRequired()
+  {
+    $this->required = true;
+    return $this;
+  }
+
+  public function withMinLen(int $minLen)
+  {
+    $this->minLen = $minLen;
+    return $this;
+  }
+
+  public function withMaxLen(int $maxLen)
+  {
+    $this->maxLen = $maxLen;
+    return $this;
+  }
+
+  /*
+  * Getters and Setters
+  */
+
+  public function getError()
+  {
+    return $this->error;
+  }
+
+  public function getName()
+  {
+    return $this->name;
+  }
+
+  /*
+  * Methods
+  */
+
+  public function isValid()
+  {
+    if ($this->required && empty($this->value)) {
+      $this->error = "$this->name is required";
+      return false;
+    }
+
+    if ($this->minLen >= 0 && !empty($this->value) && strlen($this->value) < $this->minLen) {
+      $this->error = "$this->name requires $this->minLen characters, got " . strlen($this->value);
+      return false;
+    }
+
+    if ($this->maxLen >= 0 && !empty($this->value) && strlen($this->value) > $this->maxLen) {
+      $this->error = "$this->name allows $this->maxLen characters, got " . strlen($this->value);
+      return false;
+    }
+
+    switch ($this->type) {
+      case "email":
+        if (!filter_var($this->value, FILTER_VALIDATE_EMAIL)) {
+          $this->error = "Not a valid E-Mail";
+          return false;
+        }
+        break;
+      case "number":
+        if (!filter_var($this->value, FILTER_VALIDATE_FLOAT) || !filter_var($this->value, FILTER_VALIDATE_INT)) {
+          $this->error = "Not a valid number";
+          return false;
+        }
+        break;
+    }
+
+    return true;
+  }
+}
diff --git a/tasks/oop/classes/formValidator/formValidator.php b/tasks/oop/classes/formValidator/formValidator.php
new file mode 100644
index 0000000..463df1c
--- /dev/null
+++ b/tasks/oop/classes/formValidator/formValidator.php
@@ -0,0 +1,61 @@
+<?php
+class FormValidator
+{
+  /*
+  * Private members
+  */
+
+  private array $fields;
+
+  /*
+  * Constructor
+  */
+
+  public function __construct(FieldValidator ...$fields)
+  {
+    $this->fields = $fields;
+  }
+
+  /*
+  * Fluent Style
+  */
+
+  public static function create(FieldValidator ...$fields)
+  {
+    return new FormValidator(...$fields);
+  }
+
+  /*
+  * Methods
+  */
+
+  public function isValid()
+  {
+    foreach ($this->fields as $field) {
+      if (!$field->isValid) return false;
+    }
+
+    return true;
+  }
+
+  public function getErrors()
+  {
+    $errors = [];
+
+    foreach ($this->fields as $field) {
+      if (!$field->isValid()) array_push($errors, $field->getError());
+    }
+
+    return $errors;
+  }
+
+  public function getField(string $name)
+  {
+    $field = current(array_filter($this->fields, fn ($field) => strcmp($field->getName(), $name) === 0));
+    if ($field !== false) {
+      return $field;
+    }
+
+    return "No field named $name";
+  }
+}
diff --git a/tasks/oop/hyperlink/hyperlink.php b/tasks/oop/classes/hyperlink/hyperlink.php
similarity index 100%
rename from tasks/oop/hyperlink/hyperlink.php
rename to tasks/oop/classes/hyperlink/hyperlink.php
diff --git a/tasks/oop/person/person.php b/tasks/oop/classes/person/person.php
similarity index 100%
rename from tasks/oop/person/person.php
rename to tasks/oop/classes/person/person.php
diff --git a/tasks/oop/fieldValidator/index.php b/tasks/oop/fieldValidator/index.php
new file mode 100644
index 0000000..6c838f8
--- /dev/null
+++ b/tasks/oop/fieldValidator/index.php
@@ -0,0 +1,38 @@
+<!DOCTYPE html>
+<html lang="en">
+
+<head>
+  <?php include_once "../../../base/meta.php" ?>
+
+  <title>FieldValidator Test</title>
+</head>
+
+<body>
+  <?php
+  include_once "../../../base/settings.php";
+  include_once "../../../base/headers.php";
+  Headers::html();
+
+  //Testdatei für die Klasse FieldValidator
+  include_once "../classes/fieldValidator/fieldValidator.php";
+
+  $validators = [
+    FieldValidator::create("Empty Valid", "", "string"),
+    FieldValidator::create("Empty Invalid", "", "string")->isRequired(),
+    FieldValidator::create("MinLen Valid", "ssss", "string")->withMinLen(4),
+    FieldValidator::create("MinLen Invalid", "sss", "string")->withMinLen(4),
+    FieldValidator::create("MaxLen Valid", "ssss", "string")->withMaxLen(4),
+    FieldValidator::create("MaxLen Invalid", "sssss", "string")->withMaxLen(4),
+    FieldValidator::create("E-Mail Valid", "khofmann@fu-berlin.de", "email"),
+    FieldValidator::create("E-Mail Invalid", "khofmann@fu-berlin de", "email"),
+  ];
+
+  foreach ($validators as $validator) {
+    echo "<b>" . $validator->getName() .  "</b>: ";
+    echo $validator->isValid() ? "<em>True</em>" : "<em>False</em>" . " with " . $validator->getError();
+    echo "<br />";
+  }
+  ?>
+</body>
+
+</html>
\ No newline at end of file
diff --git a/tasks/oop/formValidator/index.php b/tasks/oop/formValidator/index.php
new file mode 100644
index 0000000..5695864
--- /dev/null
+++ b/tasks/oop/formValidator/index.php
@@ -0,0 +1,46 @@
+<!DOCTYPE html>
+<html lang="en">
+
+<head>
+  <?php include_once "../../../base/meta.php" ?>
+
+  <title>FormValidator Test</title>
+</head>
+
+<body>
+  <?php
+  include_once "../../../base/settings.php";
+  include_once "../../../base/headers.php";
+  Headers::html();
+
+  //Testdatei für die Klasse FormValidator
+  include_once "../classes/fieldValidator/fieldValidator.php";
+  include_once "../classes/formValidator/formValidator.php";
+
+  $form = FormValidator::create(
+    FieldValidator::create("Empty Valid", "", "string"),
+    FieldValidator::create("Empty Invalid", "", "string")->isRequired(),
+    FieldValidator::create("MinLen Valid", "ssss", "string")->withMinLen(4),
+    FieldValidator::create("MinLen Invalid", "sss", "string")->withMinLen(4),
+    FieldValidator::create("MaxLen Valid", "ssss", "string")->withMaxLen(4),
+    FieldValidator::create("MaxLen Invalid", "sssss", "string")->withMaxLen(4),
+    FieldValidator::create("E-Mail Valid", "khofmann@fu-berlin.de", "email"),
+    FieldValidator::create("E-Mail Invalid", "khofmann@fu-berlin de", "email"),
+  );
+
+  foreach ($form->getErrors() as $error) {
+    echo "$error<br />";
+  }
+
+  ?>
+  <br />
+  <pre>
+    <?php
+    print_r($form->getField("E-Mail Valid"));
+    echo "\n\n";
+    print_r($form->getField("Name"));
+    ?>
+  </pre>
+</body>
+
+</html>
\ No newline at end of file
diff --git a/tasks/oop/hyperlink/index.php b/tasks/oop/hyperlink/index.php
index 409f47b..1d59132 100644
--- a/tasks/oop/hyperlink/index.php
+++ b/tasks/oop/hyperlink/index.php
@@ -14,7 +14,7 @@
   Headers::html();
 
   //Testdatei für die Klasse Hyperlink
-  include_once "./hyperlink.php";
+  include_once "../classes/hyperlink/hyperlink.php";
 
   //Objektinstanzen
   $link1 = new Hyperlink("https://www.google.de", "Google");
diff --git a/tasks/oop/person/index.php b/tasks/oop/person/index.php
index 8e8442d..52ba450 100644
--- a/tasks/oop/person/index.php
+++ b/tasks/oop/person/index.php
@@ -13,7 +13,7 @@
   include_once "../../../base/headers.php";
   Headers::html();
 
-  include_once "./person.php";
+  include_once "../classes/person/person.php";
   $person = new Person("John Doe", 170, new DateTime("01-01-1970"));
 
   echo $person;