Laravel ORM 关系方法'BelongsToMany' 抛出错误
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Laravel ORM relationship method 'BelongsToMany' throwing error
提问by Chris
Summary
概括
I am receiving the following error when trying to call the relationship:
我在尝试调用关系时收到以下错误：
Object of class Illuminate\Database\Eloquent\Relations\BelongsToMany could not be converted to string
类 Illuminate\Database\Eloquent\Relations\BelongsToMany 的对象无法转换为字符串
My setup is very basic, and consists of two models, Userand Role.
我的设置非常基本，包括两个模型，User和Role.
User Model [User.php]
用户模型 [User.php]
<?php
use Illuminate\Auth\UserInterface;
class User extends Eloquent implements UserInterface {
protected $table = 'users';
protected $hidden = array('password');
protected $fillable = array('id', 'username', 'password');
public function getAuthIdentifier() {
return $this->getKey();
}
public function getAuthPassword() {
return $this->password;
}
}
Role Model [Role.php]
角色模型 [Role.php]
<?php
class Role extends Eloquent {
protected $table = "roles";
protected $fillable = array(
'id',
'code',
'name'
);
public function foo() {
return $this->belongsToMany('User', 'map_role_user', 'role_id', 'user_id');
}
}
And finally I'm calling the method fooin the routes file, example:
最后我调用foo路由文件中的方法，例如：
Route::get('role', function() {
return Role::find(1)->foo();
});
回答by Daniel Albornoz
From
从
https://laravel.com/docs/5.3/eloquent-relationshipsor https://laravel.com/docs/4.2/eloquent#relationships
https://laravel.com/docs/5.3/eloquent-relationships或https://laravel.com/docs/4.2/eloquent#relationships
If a collection is cast to a string, it will be returned as JSON:
如果集合被转换为字符串，它将作为 JSON 返回：
<?php
$roles = (string) User::find(1)->roles;
回答by Chaudhry Waqas
If you dont want to add further constraints to the query then you have to use dynamic propertiesconcept. So,
如果您不想向查询添加更多约束，则必须使用dynamic properties概念。所以，
$user = App\User::find(1);
foreach ($user->posts as $post) {
//
}
If you want to add more constraints then do this
如果您想添加更多约束，请执行此操作
App\User::find(1)->posts()->where('title', 'LIKE', '%Best%')->get()
