Laravel关系函数显示为null

I'm creating a small webshop where users can create orders and sellers can see the orders. I have defined relationships but the related functions are null. This is how my tables looks like in phpmyAdmin https://imgur.com/a/C2PSmFt

This is how I have defined relationships in my models.

User.php

public function sellerOrders()
{
    return $this->hasMany(Order::class);
}

Order.php

public function user()
{
    return $this->belongsTo('App\User', 'seller_id');
}

public function products()
{
    return $this->belongsToMany('App\Product')->withPivot('quantity','total','Subtotal');
}

public function productInfo()
 {
     return $this->belongsTo('App\Product');
 }

 public function orderInfo()
 {
    return $this->belongsTo(OrderProduct::class, 'seller_id');
 }

This is my function in controller

$orders = Auth::user()->sellerOrders()->with('productInfo','orderInfo')->get();

When I dd($orders), this is what i get

 Collection {#305 ▼
 #items: array:1 [▼
 0 => Order {#286 ▼
  #table: "orders"
  #fillable: array:5 [▶]
  #connection: "mysql"
  #primaryKey: "id"
  #keyType: "int"
  +incrementing: true
  #with: []
  #withCount: []
  #perPage: 15
  +exists: true
  +wasRecentlyCreated: false
  #attributes: array:8 [▼
    "id" => 9
    "user_id" => 1
    "shipping_email" => "878888"
    "shipping_name" => "hattta"
    "shipping_city" => "kljjdjd"
    "shipped" => 0
    "created_at" => "2019-07-05 01:33:58"
    "updated_at" => "2019-07-05 01:33:58"
  ]
  #original: array:8 [▶]
  #changes: []
  #casts: []
  #dates: []
  #dateFormat: null
  #appends: []
  #dispatchesEvents: []
  #observables: []
  #relations: array:2 [▼
    "productInfo" => null
    "orderInfo" => null
  ]
  #touches: []
  +timestamps: true
  #hidden: []
  #visible: []
  #guarded: array:1 [▶]
}
]
}

How can I show productInfo and orderInfo? Your help is really appreciated.

Because You have in relation return hasMany => in orders you will have an array and since you queried it already, you have to query each item like so:

foreach($orders as $order){
    echo $order->productInfo->propertyOfProductInforTable;
    echo $order->products->name; //or whatever is in your product table relation
}

If you take a look at the attributes on the Order model from your dump, there is no field seller_id:

#attributes: array:8 [▼
"id" => 9
"user_id" => 1                      <--- There is a user_id, but not seller_id
"shipping_email" => "878888"
"shipping_name" => "hattta"
"shipping_city" => "kljjdjd"
"shipped" => 0
"created_at" => "2019-07-05 01:33:58"
"updated_at" => "2019-07-05 01:33:58"
]

You need to either add a seller_id field to the model and add the value to the database, or, perhaps easier, change your relations on the Order model so that the foreign key is user_id instead of seller_id.

Once you fix this, you should see a value for your **user** on the Order. So if you loop through $orders, you can do $order->user and it should return the user for the order.

Same thing for your productInfo. There is no product_id on the Order model, and because of the non-conventional name (i.e. it's not just 'product()'), you will need to specify the foreign key in the relationship method on the Order model. Also, don't forget to add the product_id to the Order model as fillable.

Same problem applies to your orderInfo() method - there is no seller_id on the order model to provide the relationship - same fix could apply as above.