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--- getting_started_with_laravel [03.12.2020 15:29] – Pascal Suter
+++ getting_started_with_laravel [04.12.2020 11:19] – [dump / dump and die] Pascal Suter
@@ Line 148: / Line 148: @@
   * foreign keys in should be named in the singular, lowercase and underscored form of the target table plus ''_id'' appended to it. so for example ''notebook_part_id'' if the target table is ''notebook_parts'' or ''pizza_id'' if the target table is ''pizzas''
+===== Form validation =====
+Laravel provides a nice Method for validating forms. Typically the validator is added in the Controller ''store()'' method. here is an example:
+<code php>
+    public function store(Request $request){
+        $validData = $request->validate([
+            'name' => ['required', 'string', 'max:255'],
+            'email' => ['required', 'string', 'email', 'max:255', 'unique:users'],
+            'password' => ['required', 'string', 'min:8', 'confirmed'],
+        ]);
+        // anything from here on will only be executed if the above validation was successful
+     }
+</code>
+there are many [[https://laravel.com/docs/8.x/validation#available-validation-rules|validation rules]] available already in Laravel and custom rules can be added if needed.
+also note, that the ''$validData'' variable now contains an array with the validated data in a format that is compatible with the ''create'' methods for the laravel models. So if you set up your model's ''$fillable'' property correctly and your form field names correspond to your database field names, you can pass this array straight to the ''create()'' method of your model and create a new database entry like that!
+now here are a few cool things about the validator:
+  * if it finds an invalid field, it will stop right there and laravel will show you the form page again without any further routes needed.
+  * in addition to bringing the user back to the form, laravel will provide an ''$error'' variable which can be used in the balde
+  * even better, there is a ''@error(fieldname)'' blade syntax which will do whatever follows after it if the specified field is invalid
+  * you also get a ''old(fieldname)'' function which you can use to populate your input fields with the original inputs, so the user won't have to enter eveything again.. see the eample below.
+here's an example part of a (bootstrap based) blade with a form that will show some info if the validation fails:
+<code html>
+    @if ($errors->any())
+      <div class="alert alert-danger col-12" role="alert">
+        You did not fill in all the form fields correctly, please correct or complete the Information given below
+      </div>
+    @endif
+  <form action="{{ route('address.create') }}" method="POST">
+    @csrf
+    <div class="row pt-4">
+      <div class="form-group col-12">
+        <label for="inputName">Name</label>
+        <input type="text" class="form-control @error('name') is-invalid @enderror" id="inputName" name="name" value="{{ old('name') }}">
+        <div class="invalid-feedback">Please enter your name here</div>
+      </div>
+      ....
+</code>
 ===== Tricks =====
+==== dump / dump and die ====
+this has to be the first tip :) .. there is a helper function called ''dd()'' which stands for ''dump and die''. it dumps a variable and then stops further execution of the script. this is of course extremely helpful when learning stuff and trying out things.
+you may not always want to stop the execution, so another helper called ''dump()'' comes in handy here. it produces the same output but contines the execution of your script
+to use those helpers in a blade, there are special blade syntax helpers available which make it even easier:
+<code>@dump($__data)</code>
+for example dumps all defined variables. there is also a ''@dd()'' helper available.
+note that using <code>{{ dump($__data) }}</code> won't work. there is a detailed explanation why [[https://stackoverflow.com/questions/48731507/laravel-dump-unexpected-output|on stackexchange]]
 ==== Create Model + Controller + Migration all in one step ====
   artisan make:model Pizza -mc
@@ Line 184: / Line 234: @@
 @extends('layouts.mylaout', [ 'title' => "Details for ".$section->name, 'image' => 'section_details.jpg' ])
 </code>
-and in the layout you would then simply use ''{{ $title }}'' to echo the title you passed along.
+and in the layout you would then simply use <code>{{ $title }}</code> to echo the title you passed along.
 === 2.) create a mini-section ===