Question

大家好我已经用映射制作了几个类：

class Like extends Model

/**
 * Returns like's author
 * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
 */
public function owner(){
    return $this->belongsTo('App\User');
}

/**
 * Returns tweet
 * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
 */
public function tweet(){
    return $this->belongsTo('App\Tweet');
}

Class Tweet extends Model


/**
 * Returns tweet's author
 * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
 */
public function owner(){
    return $this->belongsTo('App\User');
}

/**
 * Returns tweet's likes
 * @return \Illuminate\Database\Eloquent\Relations\HasMany
 */
public function likes(){
    return $this->hasMany('App\Like');
}

Class User extends Authenticatable
use Notifiable;

/**
 * The attributes that are mass assignable.
 *
 * @var array
 */
protected $fillable = [
    'email', 'password', 'www', 'first_name', 'last_name', 'status'
];

/**
 * The attributes that should be hidden for arrays.
 *
 * @var array
 */
protected $hidden = [
    'password',
];


/**
 * Returns user's tweets
 * @return \Illuminate\Database\Eloquent\Relations\HasMany
 */
public function tweets(){
    return $this->hasMany('App\Tweet');
}

/**
 * Returns user's likes
 * @return \Illuminate\Database\Eloquent\Relations\HasMany
 */
public function likes(){
    return $this->hasMany('App\Like');
}

现在的问题是我的两个maping无法正常工作。在Like model＆＃39; owner＆＃39;方法返回null，虽然它应该返回一条记录，＆＃39; tweet＆＃39;另一只手的方法按预期工作。

在Tweet模型中，＆＃39;所有者＆＃39;方法也返回null。所有其他方法都按预期工作。我无法找到我犯错误的地方，也无法理解为什么来自Like模型的推文方法正在工作且所有者不是......

也许迁移找到可能有帮助

public function up()
{
    Schema::create('likes', function (Blueprint $table) {
        $table->increments('id');
        $table->integer('tweet_id');
        $table->integer('user_id');
        $table->string('status');
        $table->timestamps();
    });
}


 public function up()
{
    Schema::create('tweets', function (Blueprint $table) {
        $table->increments('id');
        $table->integer('user_id');
        $table->string('content');
        $table->string('score');
        $table->string('views');
        $table->string('status');
        $table->timestamps();

 public function up()
{
    Schema::create('users', function (Blueprint $table) {
        $table->increments('id');
        $table->string('email')->unique();
        $table->string('password',60);
        $table->string('www');
        $table->string('first_name');
        $table->string('last_name');
        $table->string('status');
        $table->timestamps();
    });

Answer 1

您必须指定外键：

Schema::table('tweets', function ($table) {
    $table->integer('user_id')->unsigned();
    $table->foreign('user_id')->references('id')->on('users');
});

Answer 2

你的推文＆amp; 赞模型将owner()作为belongsTo()关系方法。哪个没问题，但您必须将外键指定为第二个参数：

/**
 * Returns like's author
 * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
 */
public function owner()
{
    return $this->belongsTo('App\User', 'user_id');
}

Laravel docs：

Eloquent通过检查关系方法的名称并使用_id为方法名称添加后缀来确定默认外键名称。

多个laravel映射，一边不能工作

2 个答案: