如何使用Laravel 5.1将空字符串更改为null? [英] How to change empty string to a null using Laravel 5.1?

问题描述

在使用Laravel 5.1的同时，我试图在使用Eloquent ORM将每个值保存在数据库中之前检查每个值.我的逻辑是，首先修剪值，如果值是空字符串""，然后将其转换为null而不是仅是空字符串.

While using Laravel 5.1, I am trying to check every value before it is saved in the database using Eloquent ORM. My logic is, first trim the value, if the value is an empty string "", then to convert it to null instead of just an empty string.

建议我创建一个Trait，该特性将覆盖setAttribute方法.

I was advised to create a Trait which will override the setAttribute method for that.

这就是我所做的

我在名为TrimScalarValues.php的文件中有一个新文件夹"app \ Traits"，其中包含以下代码

I have a new folder "app\Traits" inside of a file called TrimScalarValues.php which contains the following code

<?php

namespace App\Traits;

trait TrimScalarValues
{
    public function setAttribute($key, $value)
    {
        if (is_scalar($value)) {
            $value = $this->emptyStringToNull(trim($value));
        }

        return $this->setAttribute($key, $value);
    }


    /**
     * return null value if the string is empty otherwise it returns what every the value is
     *
    */
    private function emptyStringToNull($string)
    {
        //trim every value
        $string = trim($string);

        if ($string === ''){
           return null;
        }

        return $string;
    }
}

最后我有一个app\Models\Account.php文件，其中包含以下代码

Finally I have a app\Models\Account.php file which contains the following code

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use App\Models\industry;
use App\Traits\RecordSignature;
use App\Traits\TrimScalarValues;


class Account extends Model
{
    use RecordSignature, TrimScalarValues;
    /**
     * The database table used by the model.
     *
     * @var string
    */
    protected $table = 'accounts';

    protected $primaryKey = 'account_id';

    const CREATED_AT = 'created_on';

    const UPDATED_AT = 'modified_on';

    const REMOVED_AT = 'purged_on';


    /**
     * The attributes that are mass assignable.
     *
     * @var array
    */
    protected $fillable = ['client_id','account_name', 'company_code', 'legal_name', 'created_by','modified_by','instrucations'];

    /**
     * The attributes excluded from the model's JSON form.
     *
     * @var array
    */
    //protected $hidden = ['account_id', 'remember_token'];


    protected $guarded = ['account_id'];

    /**
     * Get the industry record associated with the account.
    */
    public function industry()
    {
        return $this->hasOne(industry, industry::primaryKey);
    }

    public function pk(){

        return $this->primaryKey;
    }

}

但是每次我更新一个值时，我都会得到一个没有错误或日志的白页.

But every time I update a value, I get a white page with no error or logs.

当我修改app\Models\Account.php并将use RecordSignature, TrimScalarValues;更改为use RecordSignature;时，我没有得到白页，但是显然这些值没有被修剪并转换为null.

When I modify the app\Models\Account.php and change use RecordSignature, TrimScalarValues; to use RecordSignature; then I do not get a white page but obviously the values are not trimmed and converted to null.

我在这里做什么错了?

推荐答案

您无法在特征中调用$this->setAttribute().相反，您想使用parent::来调用原始" setAttribute方法:

You can't call $this->setAttribute() in your trait. Instead you want to call the "original" setAttribute method by using parent:::

public function setAttribute($key, $value)
{
    if (is_scalar($value)) {
        $value = $this->emptyStringToNull(trim($value));
    }

    return parent::setAttribute($key, $value);
}

---

关于空日志，除了框架中的日志以外，您是否还检查过Web服务器日志?

---

Regarding the empty logs, have you checked the webserver log besides the one from the framework?

这篇关于如何使用Laravel 5.1将空字符串更改为null?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！