Laravel form verification can be implemented through the validate() method in the controller. 1. Use validate() to define rules such as required, email, unique, etc. to ensure data compliance; 2. You can pass in the second parameter to customize the error message, or set a global Chinese prompt in lang/zh-CN/validation.php; 3. Use the @error directive to display error messages in the Blade template, and use old() to retain the input value; 4. Advanced tips include: a) use sometimes to implement conditional verification, b) verify array fields through users.*.name syntax, c) create a form request class (php artisan make:request) to separate complex verification logic; 5. Common rules are required, string, numeric, array, confirmed, unique, exists, min, max, regex and nullable. The complete process ensures data security and user experience, ultimately achieving reliable form processing out of the box.

Laravel's form verification functions are powerful and flexible, and can help you easily ensure that the data submitted by users meets expectations. Here is a practical Laravel form validation tutorial for beginners and those who want to consolidate their foundation.

1. Basic form verification (using controller verification)

The most common way to verify is to use validate() method in the controller. Suppose you have a user registration form that requires verification of your name, email, and password.

 // public function store(Request $request) in your controller
{
    $validated = $request->validate([
        'name' => 'required|string|max:255',
        'email' => 'required|email|unique:users',
        'password' => 'required|min:8|confirmed',
    ]);

    // After verification is passed, save the user User::create($validated);

    return redirect()->route('users.index')->with('success', 'User creation succeeded!');
}

illustrate:

• required : The field must exist and is not empty.
• string : Must be a string.
• max:255 : up to 255 characters.
• email : Must be in the legal email format.
• unique:users : unique in the users table.
• min:8 : The minimum password is 8 digits.
• confirmed : There must be a corresponding password_confirmation field with the same value.

If verification fails, Laravel will automatically redirect back to the previous page and store the error message into the session.

2. Customize the error message

The default error message is in English, you can customize more friendly tips:

 $validated = $request->validate([
    'name' => 'required|string|max:255',
    'email' => 'required|email|unique:users',
    'password' => 'required|min:8|confirmed',
], [
    'name.required' => 'The name cannot be empty',
    'email.email' => 'Please enter a valid email address',
    'password.min' => 'Password requires at least 8 characters',
    'password.confirmed' => 'The password entered twice is inconsistent',
]);

You can also set global Chinese prompts in lang/zh-CN/validation.php to make the entire project unified.

3. Display error message in Blade template

In the view, use the $errors variable to display verification failure information:

 <!-- resources/views/users/create.blade.php -->
<form method="POST" action="{{ route(&#39;users.store&#39;) }}">
    @csrf

    <div>
        <label>Name</label>
        <input type="text" name="name" value="{{ old(&#39;name&#39;) }}">
        @error(&#39;name&#39;)
            <span style="color: red;">{{ $message }}</span>
        @enderror
    </div>

    <div>
        <label>Email</label>
        <input type="email" name="email" value="{{ old(&#39;email&#39;) }}">
        @error(&#39;email&#39;)
            <span style="color: red;">{{ $message }}</span>
        @enderror
    </div>

    <div>
        <label>Password</label>
        <input type="password" name="password">
        @error(&#39;password&#39;)
            <span style="color: red;">{{ $message }}</span>
        @enderror
    </div>

    <div>
        <label>Confirm password</label>
        <input type="password" name="password_confirmation">
    </div>

    <button type="submit">Submit</button>
</form>

• @error('field') will check for errors in the field.
• old('name') retains user input and avoids refilling the form.

4. Advanced verification skills

a) Conditional verification (sometimes required, sometimes not required)

Use the sometimes rules:

 $request->validate([
    'phone' => 'sometimes|required|numeric',
]);

Verify only if phone field exists.

b) Verify array fields

For example, adding users in batches:

 $request->validate([
    'users.*.name' => 'required|string',
    'users.*.email' => 'required|email',
]);

c) Use Form Request class—suitable for complex verification

Generate a special request class:

 php artisan make:request StoreUserRequest

Edit the generated app/Http/Requests/StoreUserRequest.php :

 public function rules()
{
    Return [
        'name' => 'required|string|max:255',
        'email' => 'required|email|unique:users',
        'password' => 'required|min:8|confirmed',
    ];
}

public function messages()
{
    Return [
        'name.required' => 'Name required',
        'email.unique' => 'This email has been registered',
    ];
}

Use in the controller:

 public function store(StoreUserRequest $request)
{
    User::create($request->validated());
    return redirect()->route('users.index');
}

This approach is clearer and is especially suitable for large projects.

5. Quick check of common verification rules

Basically that's it. Laravel's verification mechanism is out of the box, combined with validate() , custom messages and Blade error display, can quickly achieve safe and reliable form processing. It is not complicated, but it is easy to ignore details. For example, confirmed requires corresponding fields, and unique should pay attention to ignoring the current user when updating, etc.

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