如何在 Laravel 中检查用户电子邮件是否存在？

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有多种方法可以测试电子邮件是否存在。一种方法是使用校验器类。为了使用校验器，你需要像下面这样包含类；

use Illuminate\Support\Facades\Validator;

示例 1

该示例演示了如何使用校验器来检查电子邮件是否已注册。

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request; use Illuminate\Support\Facades\Validator;
class UserController extends Controller { 
   public function index() { 
      $inputValues['email'] = "[email protected]";

      // checking if email exists in ‘email’ in the ‘users’ table $rules = array('email' => 'unique:users,email');

      $validator = Validator::make($inputValues, $rules);

      if ($validator->fails()) { 
         echo 'The email already exists'; 
      } else { 
         echo 'The email is not registered'; 
      } 
   } 
}

输出

上述代码的输出为 -

The email already exists

示例 2

现在，让我们尝试一个用户表中不存在的电子邮件。

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Validator;

class UserController extends Controller{
   public function index() {
      $inputValues['email'] = "[email protected]";
      // checking if email exists in ‘email’ in the ‘users’ table
      $rules = array('email' => 'unique:users,email');
      $validator = Validator::make($inputValues, $rules);

      if ($validator->fails()) {
         echo 'The email already exists';
      } else {
         echo 'The email is not registered';
      }
   }
}

输出

上述代码的输出为 -

The email is not registered

示例 3

你可以利用 Eloquent 模型来检查电子邮件是否存在于用户表中

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use App\Models\User;

class UserController extends Controller{
   public function index() {
      $email = "[email protected]";
      $userEmailDetails = User::where('email', '=', $email)->first();
      
      if ($userEmailDetails === null) {
         echo 'The email is not registered';
      } else {
         echo 'The email already exists';
     }
   }
}

输出

上述代码的输出为 -

The email already exists

示例 4

使用 Laravel eloquent 模型的 count() 方法 -

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use App\Models\User;

class UserController extends Controller {
   public function index() {
      $email = "[email protected]";
      if (User::where('email', '=', $email)->count() > 0) {
         echo "Email Exists";
      } else {
         echo "Email is not registered";
      }
   }
}

输出

上述代码的输出为 -

Email Exists

示例 5

使用 Laravel eloquent 模型的 exists() 方法 -

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use App\Models\User;

class UserController extends Controller{
   public function index() {
      $email = "[email protected]";
      if (User::where('email', '=', $email)->exists()) {
         echo "Email Exists";
      } else {
         echo "Email is not registered";
      }
   }
}

输出

上述代码的输出为 -

Email Exists