polymorphism laravel code example

Example 1: one to many laravel

For example, a blog post may have an infinite number of comments. And a single
comment belongs to only a single post  

class Post extends Model
{
    public function comments()
    {
        return $this->hasMany('App\Models\Comment');
    }
}

class Comment extends Model
{
    public function post()
    {
        return $this->belongsTo('App\Models\Post');
    }
}

Example 2: laravel polymorphic model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Image extends Model
{
    /**
     * Get the owning imageable model.
     */
    public function imageable()
    {
        return $this->morphTo();
    }
}

class Post extends Model
{
    /**
     * Get the post's image.
     */
    public function image()
    {
        return $this->morphOne('App\Image', 'imageable');
    }
}

class User extends Model
{
    /**
     * Get the user's image.
     */
    public function image()
    {
        return $this->morphOne('App\Image', 'imageable');
    }
}

Example 3: morph relation laravel

You may register the morphMap in the boot function of your 
App\Providers\AppServiceProvider class or create a separate service provider 
if you wish.

use Illuminate\Database\Eloquent\Relations\Relation;

Relation::morphMap([
    'post' => 'App\Models\Post',
    'video' => 'App\Models\Video',
]);

Example 4: laravel poly morphic relationship

class Mechanic extends Model
{
    /**
     * Get the car's owner.
     */
    public function carOwner()
    {
        return $this->hasOneThrough(
            'App\Owner',
            'App\Car',
            'mechanic_id', // Foreign key on cars table...
            'car_id', // Foreign key on owners table...
            'id', // Local key on mechanics table...
            'id' // Local key on cars table...
        );
    }
}