C＃Mongo驱动程序-如何进行不区分大小写的搜索

Question

我需要获取所有由用户列表创建的井。以下是我为此要求编写的代码。但是x.CreatedBy.ToLower（）引发下面列出的异常：

            FilterDefinition<WellInfoDocument> userFilter = builder.Where(x => users.Contains(x.CreatedBy.ToLower()));
            var documentList = await GetCollection<WellInfoDocument>().FindAsync<WellInfoDocument>(userFilter);```


 System.ArgumentException: Unsupported filter: Contains(value(System.Collections.Generic.List`1[System.String])).
   at MongoDB.Driver.Linq.Translators.PredicateTranslator.Translate(Expression node)
   at MongoDB.Driver.Linq.Translators.PredicateTranslator.Translate(Expression node, IBsonSerializerRegistry serializerRegistry)
   at MongoDB.Driver.MongoCollectionImpl`1.CreateFindOperation[TProjection](FilterDefinition`1 filter, FindOptions`2 options)
   at MongoDB.Driver.MongoCollectionImpl`1.FindAsync[TProjection](IClientSessionHandle session, FilterDefinition`1 filter, FindOptions`2 options, CancellationToken cancellationToken)
   at MongoDB.Driver.MongoCollectionImpl`1.<>c__DisplayClass43_0`1.<FindAsync>b__0(IClientSessionHandle session)
   at MongoDB.Driver.MongoCollectionImpl`1.UsingImplicitSessionAsync[TResult](Func`2 funcAsync, CancellationToken cancellationToken)


Any suggestions to fix is welcome. TIA

Answer 1

给$in过滤器去。

 var filter = Builders<WellInfoDocument>.Filter.In(x => x.CreatedBy.ToLower(),users.Select(x => x.Id).ToList());
 var documentList = await GetCollection<WellInfoDocument>().FindAsync<WellInfoDocument>(filter);

不确定您的类型或外观，但是您应该可以从此示例中得出结论。