根据Laravel中的表单输入验证复合模型字段的唯一性

编写自己的规则。它可以看起来像这样：

'unique_composite:table,field1,field2,field3,...,fieldN'

在表名之后枚举的字段将被连接起来，并根据组合值进行检查。验证规则如下所示：

Validator::extend('unique_composite', function ($attribute, $value, $parameters)
{
    // Get table name from first parameter
    $table  = array_shift($parameters);
    $fields = implode(',', $parameters);
    // Build the query that searches the database for matches
    $matches = DB::table($table)
                ->where(DB::raw('CONCAT_WS(" ", ' . $fields . ')'), $value)
                ->count();
    // Validation result will be false if any rows match the combination
    return ($matches == 0);
});

在你的验证器中，你可以有这样的东西：

$validator = Validator::make(
    array('full_name' => $firstName + ' ' + $lastName),
    array('full_name' => 'unique_composite:users,first_name,last_name')
);

使用此规则，您可以使用任意数量的字段，而不仅仅是两个。

我最终扩展了Validator类来定义自定义验证器规则。我在应用程序的first_name字段中检查它，主要是因为我不想在生成全名时做额外的工作。除了在考虑了这个问题后没有必要将其设置为复合值之外，我只是将其设置成检查指定字段的所有值的AND。您可以指定任意数量的字段，如果其中一个字段不存在于验证器数据中，则会引发异常。我甚至不确定这是否可以单独使用现有的unique规则来实现，但无论如何，这都是一个很好的练习。

'first_name' => 'unique_multiple_fields:members,first_name,last_name'

我的验证器子类代码：

use Illuminate'Validation'Validator as IlluminateValidator;
class CustomValidatorRules extends IlluminateValidator
{
    /**
     * Validate that there are no records in the specified table which match all of the 
     * data values in the specified fields. Returns true iff the number of matching 
     * records is zero.
     */
    protected function validateUniqueMultipleFields( $attribute, $value, $parameters )
    {
        if (is_null($parameters) || empty($parameters)) {
            throw new 'InvalidArgumentException('Expected $parameters to be a non-empty array.');
        }
        if (count($parameters) < 3) {
            throw new 'InvalidArgumentException('The $parameters option should have at least 3 items: table, field1, field2, [...], fieldN.');
        }
        // Get table name from first parameter, now left solely with field names.
        $table = array_shift($parameters);
        // Uppercase the table name, remove the 's' at the end if it exists
        // to get the class name of the model (by Laravel convention).
        $modelName = preg_replace("/^(.*)([s])$/", "$1", ucfirst($table));
        // Create the SQL, start by getting only the fields specified in parameters
        $select = $modelName::select($parameters);
        // Generate the WHERE clauses of the SQL query.
        foreach ($parameters as $fieldName) {
            $curFieldVal = ($fieldName === $attribute) ? $value : $this->data[$fieldName];
            if (is_null($curFieldVal)) {
                // There is no data for the field specified, so fail.
                throw new 'Exception("Expected `{$fieldName}` data to be set in the validator.");
            }
            // Add the current field name and value
            $select->where($fieldName, '=', $curFieldVal);
        }
        // Get the number of fields found
        $numFound = $select->count();
        return ($numFound === 0);
    }
}

如果你好奇的话，我确实使用了我最初研究的复合方法来实现它。代码如下。事实证明，"分隔符"完全没有意义，因此我最终将其重构为使用上面指定的多字段方法。

use Illuminate'Validation'Validator as IlluminateValidator;
class CustomValidatorRules extends IlluminateValidator
{
    /**
     * Validate that the final value of a set of fields - joined by an optional separator -
     * doesn't match any records in the specified table. Returns true iff the number of
     * matching records is zero.
     */
    protected function validateUniqueComposite( $attribute, $value, $parameters )
    {
        if (is_null($parameters) || empty($parameters)) {
            throw new 'InvalidArgumentException('Expected $parameters to be a non-empty array.');
        }
        if (count($parameters) < 3) {
            throw new 'InvalidArgumentException('The $parameters option should have at least 3 items: table, field1, field2, [...], fieldN.');//, [separator].');
        }
        // Get table name from first parameter
        $table = array_shift($parameters);
        // Determine the separator
        $separator = '';
        $lastParam = array_pop($parameters);
        if (! isset($this->data[$lastParam])) {
            $separator = $lastParam;
        }
        // Get the names of the rest of the fields.
        $fields = array();
        foreach ($parameters as $fieldName) {
            array_push($fields, $table . "." . $fieldName);
        }
        $fields = implode(', ', $fields);
        $dataFieldValues = array();
        foreach ($parameters as $fieldName) {
            $curFieldVal = ($fieldName === $attribute) ? $value : $this->data[$fieldName];
            if (is_null($curFieldVal)) {
                throw new 'Exception("Expected `{$fieldName}` data.");
            }
            array_push($dataFieldValues, $curFieldVal);
        }
        $compositeValue = implode($separator, $dataFieldValues);
        // Uppercase the table name, remove the 's' at the end if it exists
        // to get the class name of the model (by Laravel convention).
        $modelName = preg_replace("/^(.*)([s])$/", "$1", ucfirst($table));
        $raw = 'DB::raw("concat_ws('" . $separator . "', " . $fields . ")");
        $model = new $modelName;
        // Generate the SQL query
        $select = $modelName::where($raw, '=', $compositeValue);
        $numFound = $select->count();
        return ($numFound === 0);
    }
}

在不创建自定义验证器的情况下，您还可以指定更多将添加为"其中"；子句到查询和do：

'first_name' => 'required|unique:table_name,first_name,null,id,last_name,'.$data['last_name'],
'last_name' => 'required|unique:table_name,last_name,null,id,first_name,'.$data['first_name'],

这样，first_name的唯一性将仅在last_name等于输入的last_name（在我们的示例中为$data['last_name']）的行上强制执行。

CCD_ 14的唯一性也是如此。

如果您想强制唯一规则忽略给定的ID，只需将null替换为该特定的ID即可。

参考：http://laravel.com/docs/4.2/validation#rule-唯一