我正在从DB中提取疾病并在前端显示复选框:
<div class="col-lg-12 col-md-12 col-sm-12 col-xs-12">
@foreach($diseases as $disease)
<div class="col-md-6">
<div class="form-group">
<label>{{ Form::checkbox('diseases','0','',
['class' => 'grey','data-id'=> $disease->id]) }}
{{$disease->title}}
</label>
<div class="clearfix"></div>
</div>
</div>
@endforeach
</div>
提交表单后,我得到了 $request->diseases
的结果:
1:"1"
2:"1"
3:"0"
4:"1"
5:"0"
6:"0"
...
其中第一个数字代表 disease_id
,另一个代表是否选中了复选框 . 与数据透视表的关系在模型中正确进行,我在控制器中尝试做的是:
if ($request->has('diseases')) {
$patient->diseases()->sync($request->diseases);
}
但这失败了,错误:
Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key
constraint fails (`db_name`.`disease_patient`, CONSTRAINT `disease_patient_patient_id_foreign`
FOREIGN KEY (`patient_id`) REFERENCES `patients` (`id`) ON DELETE CASCADE) (SQL: insert into
`disease_patient` (`disease_id`, `patient_id`)
values (17, {"1":"0","2":"0","3":"1","4":"1","5":"1","6":"1","7":"1","8":"1","9":"0","10":"1","11":"0","12":"1","13":"0","14":"0","15":"0","16":"0","17":"0","18":"0","19":"0","20":"0","21":"0","22":"0","23":"0"}))
Patient
模型中的关系:
protected $guarded = ['id'];
public function diseases()
{
return $this->belongsToMany('App\Disease', 'disease_patient', 'disease_id', 'patient_id');
}
EDIT:
当我做:
$diseases = array_keys(array_filter(json_decode($request->diseases, true)));
return $diseases;
我得到的ID列表如下:
0:1
1:2
2:8
3:14
4:15
5:21
并且错误:
(SQL: insert into `disease_patient` (`disease_id`, `patient_id`) values (33, 1))
每次请求都会 disease_id
递增
1 回答
这里的问题是
sync
方法不应该是一个关联数组 . 您应该将一个包含要附加的疾病ID的数组传递给它 . 为此,您需要预处理阵列:如果
$request->diseases
返回Laravel集合,则可能需要先调用toArray()
或将其强制转换为数组 .参考:https://laravel.com/docs/5.4/eloquent-relationships#inserting-and-updating-related-models的"Syncing Associations"部分