只使用LINQ检查DateTime？（可空？）时的日期条件

Question

我需要检查当前日期是否有任何记录。但AddOn是可以约会的日期。如果我检查下面的条件是抛出错误，因为我正在尝试从null获取日期。

var cusRelationships = SvcClient.Client.Context.CusRelationships.Where(c =>
             c.CustomerId == identity.rCustomerId &&
             c.AddedOn.Value.Date == DateTime.Now.Date).Select(c => c).ToList();

如何比较当前日期的日期？

Answer 1

在使用Value之前检查null。

var cusRelationships = SvcClient.Client.Context.CusRelationships.Where(c =>
                 c.CustomerId == identity.rCustomerId &&
                 c.AddedOn.HasValue &&
                 c.AddedOn.Value.Date == DateTime.Now.Date).Select(c => c).ToList();

Answer 2

var cusRelationships = SvcClient.Client.Context.CusRelationships
    .Where(c =>
               c.CustomerId == identity.rCustomerId &&
               c.AddedOn.HasValue &&
               c.AddedOn.Value.ToShortDateString() == DateTime.Now.ToShortDateString())
    .Select(c => c)
    .ToList();