《PHP应用：Yii2使用表单上传文件的实例代码》要点：
本文介绍了PHP应用：Yii2使用表单上传文件的实例代码，希望对您有用。如果有疑问，可以联系我们。

PHP编程yii2用表单上传文件经常用到的,该怎样上传呢?

PHP编程1、单个文件上传

PHP编程首先建立一个模型models/UploadForm.php,内容如下

PHP编程
namespace app\models;
use yii\base\Model;
use yii\web\UploadedFile;
/**
 * UploadForm is the model behind the upload form.
 */
class UploadForm extends Model
{
  /**
   * @var UploadedFile file attribute
   */
  public $file;
  /**
   * @return array the validation rules.
   */
  public function rules()
  {
    return [
      [['file'],'file'],];
  }
}

PHP编程再建立一个视图文件,内容如下

PHP编程
<?php
use yii\widgets\ActiveForm;
?>
<?php $form = ActiveForm::begin(['options' => ['enctype' => 'multipart/form-data']]) ?>
<?= $form->field($model,'file')->fileInput() ?>
<button>Submit</button>
<?php ActiveForm::end() ?>

PHP编程最后建立控制器文件,内容如下

PHP编程
namespace app\controllers;
use Yii;
use yii\web\Controller;
use app\models\UploadForm;
use yii\web\UploadedFile;
class SiteController extends Controller
{
  public function actionUpload()
  {
    $model = new UploadForm();
    if (Yii::$app->request->isPost) {
      $model->file = UploadedFile::getInstance($model,'file');
      if ($model->file && $model->validate()) {        
        $model->file->saveAs('uploads/' . $model->file->baseName . '.' . $model->file->extension);
      }
    }
    return $this->render('upload',['model' => $model]);
  }
}

PHP编程注意这里我们没有用model->load(…),而是用了UploadedFile::getInstance(…).区别是后者不会执行$model->validate(),所以需要手动的去执行$model->validate()来检验数据的合法性.如果检验通过了,上传的文件保存在uploads文件夹下,即web目录下的uploads里.

PHP编程一些可选的配置选项

PHP编程上传文件不能为空

PHP编程
public function rules()
{
  return [
    [['file'],'file','skipOnEmpty' => false],];
}

PHP编程上传类型,不仅可以根据扩展名检验,还可以根据文件的内容进行检验

PHP编程
public function rules()
{
  return [
    [['file'],'extensions' => 'jpg,png','mimeTypes' => 'image/jpeg,image/png',],];
}

PHP编程2、多文件上传

PHP编程如果你想一次上传多个文件,只需调节几个参数就可以达到目的

PHP编程Model：

PHP编程
class UploadForm extends Model
{
  /**
   * @var UploadedFile|Null file attribute
   */
  public $file;
  /**
   * @return array the validation rules.
   */
  public function rules()
  {
    return [
      [['file'],'maxFiles' => 10],// <--- here!
    ];
  }
}

PHP编程View：

PHP编程
<?php
use yii\widgets\ActiveForm;
$form = ActiveForm::begin(['options' => ['enctype' => 'multipart/form-data']]);
?>
<?= $form->field($model,'file[]')->fileInput(['multiple' => true]) ?>
  <button>Submit</button>
<?php ActiveForm::end(); ?>

PHP编程与单文件上传不同的是下面这句

PHP编程
$form->field($model,'file[]')->fileInput(['multiple' => true])

PHP编程Controller:

PHP编程
namespace app\controllers;
use Yii;
use yii\web\Controller;
use app\models\UploadForm;
use yii\web\UploadedFile;
class SiteController extends Controller
{
  public function actionUpload()
  {
    $model = new UploadForm();
    if (Yii::$app->request->isPost) {
      $model->file = UploadedFile::getInstances($model,'file');
      if ($model->file && $model->validate()) {
        foreach ($model->file as $file) {
          $file->saveAs('uploads/' . $file->baseName . '.' . $file->extension);
        }
      }
    }
    return $this->render('upload',['model' => $model]);
  }
}

PHP编程这样就可以实现多文件上传了.

PHP编程参考https://github.com/yiisoft/yii2/blob/master/docs/guide/input-file-upload.md

PHP编程以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家PHP.