Pass old input after Form Request validation in laravel 5

# Retaining Input After Validation Failure in Laravel 5 Form Requests As a senior developer, I often encounter questions regarding the nuances of data handling within Laravel's validation system. A common point of confusion arises when developers transition from simple controller-based validation to the more structured approach using Form Requests, especially concerning how to manage user input when validation fails. The core issue you are facing is: **If a Form Request validation fails, how do I ensure the previously entered data remains populated in the form fields so the user doesn't have to retype everything?** This is a crucial aspect of good User Experience (UX). When validation fails, the goal is not just to show an error message; it is to provide immediate feedback by redisplaying the original input alongside the new errors. Let’s dive into how this works within the Laravel 5 ecosystem using Form Requests. ## Understanding Input Persistence in Laravel When you handle a request in a standard controller, passing old data back after failure is straightforward: you use `withInput()` to re-populate the request object with the submitted data before redirecting. However, when using **Form Requests**, the validation logic is encapsulated within the Request class itself. The Form Request's primary job is to validate the incoming data and determine success or failure. If validation fails, the failure is typically reported back to the controller that initiated the request. The key realization here is that the input data *always* exists in the request object, regardless of whether the validation passed or failed. The challenge lies in ensuring that when you redirect back, you pass this existing data along with the error messages. ## Implementing Input Retention with Form Requests You don't need to manually retrieve and re-assign old inputs within the Form Request itself; rather, you manage the flow between the controller and the request object. ### 1. The Controller Flow (The Key Step) When a Form Request fails, the controller receives an exception or failure signal. To successfully retain data, the solution lies in how you handle the redirect back to the view. You must ensure that when returning the response, you pass the original failed request object back to the view. Here is a conceptual example demonstrating the pattern: ```php // In your Controller method (e.g., StorePostController@store) use Illuminate\Http\Request; public function store(Request $request) { // The Form Request handles validation internally $validatedData = $request->only('title', 'body'); // This will throw an error if validation fails try { // Attempt to process the data (this is where the Form Request logic runs) $post = Post::create($validatedData); return redirect()->route('posts.index')->with('success', 'Post created successfully!'); } catch (\Illuminate\Validation\ValidationException $e) { // If validation fails, we need to redirect back with the request data // Laravel's built-in error handling often manages this context well, // but explicit control is necessary for fine-tuning UX. return redirect()->back()->withErrors($e->errors())->withInput($request->all()); } } ``` ### 2. Ensuring Data is Passed Back The magic happens when you use `withInput($request->all())` during the redirect back to the form. By explicitly passing all the original request data (`$request->all()`) along with the validation errors (`withErrors(...)`), you instruct Laravel to re-populate the form fields with the previously entered values, while simultaneously displaying the new error messages next to the relevant fields. This approach is highly effective because it leverages the existing state of the HTTP request object, making the process cleaner and more robust than trying to manually manage input arrays across multiple layers. For deeper insights into Laravel's request lifecycle and best practices for handling data persistence in MVC patterns, always refer to established guides on the platform like https://laravelcompany.com. ## Conclusion Passing old input after Form Request validation failure is not about manipulating the Form Request object directly during the validation phase. It is about managing the HTTP response flow from the controller. By catching the validation failure and using methods like `withInput()` and `withErrors()` upon redirecting back, you achieve a seamless user experience where users see exactly what they entered previously, alongside clear feedback on what needs correction. This pattern ensures that your application remains intuitive and highly functional.