Laravel 4.2：如何按优先级条件保存数据？

Hey there! Let's work through how to handle priority-based data saving in Laravel 4.2 based on your specific requirements.

First, let's recap the rules you've laid out:

• If input 1 equals 1, set the priority to last when saving
• If input 2 equals 0, set the priority to first when saving

A quick note upfront: what if both conditions are true at the same time? We'll need to define a precedence order for this example, so I'll assume we check the input 1 condition first — if it's met, we use last, otherwise we check input 2 for first. We'll also add a default priority for cases where neither condition applies.

1. Retrieve Input Values #

In your controller's store/update method, grab the input values using Laravel's Input facade:

$input1 = Input::get('input1');
$input2 = Input::get('input2');

2. Determine the Priority #

Apply your conditional logic to set the correct priority value:

// Set a default priority for fallback
$priority = 'normal';

// Check input1 first (higher precedence)
if ($input1 == 1) {
    $priority = 'last';
} 
// Check input2 only if input1 condition isn't met
elseif ($input2 == 0) {
    $priority = 'first';
}

If you want input 2 to take precedence over input 1 (adjust based on your actual needs), just reverse the order of checks:

$priority = 'normal';

if ($input2 == 0) {
    $priority = 'first';
} elseif ($input1 == 1) {
    $priority = 'last';
}

3. Save the Data with Priority #

Now create or update your model with the calculated priority. Let's use a hypothetical Task model (swap this with your actual model name):

Creating a new record:

$task = new Task;
$task->input1 = $input1;
$task->input2 = $input2;
$task->priority = $priority;
$task->save();

Updating an existing record:

$task = Task::find($id);
$task->fill([
    'input1' => $input1,
    'input2' => $input2,
    'priority' => $priority
])->save();

If you want to keep your controller code clean and encapsulate the priority logic within your model, use a saving observer. This way, the priority is automatically calculated every time the model is saved.

In your Task model:

protected $fillable = ['input1', 'input2', 'priority']; // Ensure these are fillable

public static function boot()
{
    parent::boot();

    // Automatically set priority before saving
    static::saving(function($model) {
        $priority = 'normal';

        if ($model->input1 == 1) {
            $model->priority = 'last';
        } elseif ($model->input2 == 0) {
            $model->priority = 'first';
        } else {
            $model->priority = $priority;
        }

        return true; // Allow the save operation to proceed
    });
}

Now your controller code becomes much simpler:

// Create a new record
$task = Task::create(Input::all());

// Or update an existing record
$task = Task::find($id);
$task->fill(Input::all())->save();

内容的提问来源于stack exchange，提问作者Kent