自定义校验器

Yii提供了一套内置表单校验器，基本覆盖了所有典型的开发需求，并且是高度可配置的。但是，在一些情况下，开发者可能需要创建一个自定义校验器。

本小节会给出一个例子，创建一个检查单词个数的独立校验器。

准备

按照官方指南http://www.yiiframework.com/doc-2.0/guide-start-installation.html的描述，使用Composer包管理器创建一个新的应用。

如何做…

1. 创建一个独立校验器@app/components/WordsValidator.php：

<?php
namespace app\components;
use yii\validators\Validator;
class WordsValidator extends Validator
{
    public $size = 50;
    public function validateValue($value){
        if (str_word_count($value) > $this->size) {
            return ['The number of words must be less than {size}', ['size' => $this->size]];
        }
        return false;
    }
}

1. 创建一个Article模型@app/models/Article.php：

<?php
namespace app\models;
use app\components\WordsValidator;
use yii\base\Model;
class Article extends Model
{
    public $title;
    public function rules()
    {
        return [
            ['title', 'string'],
            ['title', WordsValidator::className(), 'size' =>
                10],
        ];
    }
}

1. 创建@app/controllers/ModelValidationController.php：

<?php
namespace app\controllers;
use app\models\Article;
use yii\helpers\Html;
use yii\web\Controller;
class ModelValidationController extends Controller
{
    private function getLongTitle()
    {
        return 'There is a very long content for current article, '.'it should be less then ten words';
    }
    private function getShortTitle()
    {
        return 'There is a shot title';
    }
    private function renderContentByModel($title)
    {
        $model = new Article();
        $model->title = $title;
        if ($model->validate()) {
            $content = Html::tag('div', 'Model is valid.',[
                'class' => 'alert alert-success',
            ]);
        } else {
            $content = Html::errorSummary($model, [
                'class' => 'alert alert-danger',
            ]);
        }
        return $this->renderContent($content);
    }
    public function actionSuccess()
    {
        $title = $this->getShortTitle();
        return $this->renderContentByModel($title);
    }
    public function actionFailure()
    {
        $title = $this->getLongTitle();
        return $this->renderContentByModel($title);
    }
}

1. 访问index.php?r=model-validation/success来运行modelValidation控制器的success动作：

1. 访问index.php?r=model-validation/failure来运行modelValidation控制器的failure动作：

1. 创建@app/controllers/AdhocValidationController.php：

<?php
namespace app\controllers;
use app\components\WordsValidator;
use app\models\Article;
use yii\helpers\Html;
use yii\web\Controller;
class AdhocValidationController extends Controller
{
    private function getLongTitle()
    {
        return 'There is a very long content for current article, '.'it should be less then ten words';
    }
    private function getShortTitle()
    {
        return 'There is a shot title';
    }
    private function renderContentByTitle($title)
    {
        $validator = new WordsValidator([
            'size' => 10,
        ]);
        if ($validator->validate($title, $error)) {
            $content = Html::tag('div', 'Value is valid.',[
                'class' => 'alert alert-success',
            ]);
        } else {
            $content = Html::tag('div', $error, [
                'class' => 'alert alert-danger',
            ]);
        }
        return $this->renderContent($content);
    }
    public function actionSuccess()
    {
        $title = $this->getShortTitle();
        return $this->renderContentByTitle($title);
    }
    public function actionFailure()
    {
        $title = $this->getLongTitle();
        return $this->renderContentByTitle($title);
    }
}

1. 访问index.php?r=adhoc-validation/success来运行adhocValidation控制器的success动作：

1. 访问index.php?r=adhoc-validation/failure来运行adhocValidation控制器的failure动作：

工作原理

首先我们创建了一个独立的校验器，它会使用str_word_count函数来检查单词的数量，然后演示了两个使用例子：

• 作为Article模型的校验规则使用这个校验器
• 作为一个特定的校验器使用这个校验器

参考

欲了解更多信息，参考如下链接：

• http://www.yiiframework.com/doc-2.0/guide-input-validation.html
• http://www.yiiframework.com/doc-2.0/guide-tutorial-corevalidators.html