如何为4个组合的唯一列创建自定义验证规则 [英] How to create custom validation rule for 4 combinedly unique columns

问题描述

由于Laravel的默认 unique:tablename 验证规则仅允许两列；在两个以上的唯一列的情况下，它直接使用

Since Laravel's default unique:tablename validation rule allows only two columns; in scenarios where more than two columns are unique, it directly throws the QueryException with SQLSTATE errorcode 23000. As a temporary workaround I am catching the exception and throwing a warning like this:

try{
    //My query that might throw an exception for a duplicate entry
} catch (\Exception $e){
    return $e->getCode() == 23000 ?
           redirect()->back()->with('warning','Duplicate entry') :
           redirect()->back()->with('error','Unknown Error Occurred');
}

问题是，对于其他所有错误代码不是23000的情况，我只会看到一条错误消息Unknown Error Occurred而不是

The problem is, for every other scenarios where the errorcode is not 23000, I will only see an error message Unknown Error Occurred instead of Whoops. Clearly, debugging will be a nightmare.

所以我在寻找替代方案.我必须选择两个选项之一:a)使用第三方软件包，或者，b)创建自定义验证规则

So I looked for alternatives. I had to pick one of two options: a) Use a third party package or, b) Create a custom validation rule

我选择了选项b.但是我在为自己打造自己而苦苦挣扎.当我看一个示例(一次内联规则)时:

I chose option b. But I am struggling with how I can construct one myself. When I looked at an example (for one-time inline rule):

$validator = Validator::make($request->all(), [
    'title' => [
       'required',
       'max:255',
        function($attribute, $value, $fail) {
            if ($value === 'foo') {
                return $fail($attribute.' is invalid.');
            }
        },
    ],
]);

...我意识到该规则只能应用于单个属性和值.但是我有4个属性和值来检查它们是否确实是唯一条目.我该怎么办?

...I realized that the rule can be applied to a single attribute and value only. But I have 4 attributes and values to check if they are indeed a unique entry. How can I do that?

推荐答案

我这样使用，

public function store(Request $req)
{
    $column1 = $req->input('column1');
    $column2 = $req->input('column2');
    $column3 = $req->input('column3');
    $column4 = $req->input('column4');


    $whereData = [
        ['column1', $column1],
        ['column2', $column2],
        ['column3', $column3],
        ['column4', $column4]
    ];

    $count = DB::table('yourtablename')->where($whereData)
                                ->count();

    if($count > 0){
        // The combined is not unique
        //send error message
    }else{
        //do whatever u need
    }

}

您也可以在AppServiceProvider的启动方法中实现此功能.

You may implement this in AppServiceProvider's boot method also.

将此代码添加到您的启动方法中:

Add this code to your boot method:

Validator::extend('uniqueofFourColumns', function ($attribute, $value, $parameters, $validator) {

    $whereData = [
        ['column1', $value],
        ['column2', $parameters[0]],
        ['column3', $parameters[1]],
        ['column4', $parameters[2]]
    ];

    $count = DB::table('yourtablename')->where($whereData)->count();

    return $count === 0;
});

然后您可以在需要的地方使用uniqueofFourColumns此规则:

Then u may use uniqueofFourColumns this rule wherever u need:

'column1' => 'uniqueofFourColumns:'.{{$request->column2}}.', '.{{$request->column3}}.', '.{{$request->column4}}

这篇关于如何为4个组合的唯一列创建自定义验证规则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！