如果条目文本为空，则跳过部分查询

Question

我有一个查询

            return uow.CustomerRepo
            .Get()
            .Where
            (
                c=>
                    c.Firstname.StartsWith(customerSearch.Initial) &&
                    c.Surname  == customerSearch.Surname           &&                        
                    c.Email    == customerSearch.Email             &&
                    c.Postcode == customerSearch.PostCode
            )

是否有办法跳过查询的部分，如果在customerSearch的东西是空的?

所以我想跳过 这部分

c.Surname  == customerSearch.Surname

如果

customerSearch.Surname

空

Answer 1

您可以通过显式检查customerSearch部分的条件来做到这一点:

.Where
(
    c=>
        (customerSearch.Initial == null || c.Firstname.StartsWith(customerSearch.Initial)) &&
        (customerSearch.Surname == null || c.Surname  == customerSearch.Surname)           &&                        
        (customerSearch.Email == null || c.Email    == customerSearch.Email)             &&
        (customerSearch.PostCode == null || c.Postcode == customerSearch.PostCode)
)

如果您需要检查空字符串而不是null，请相应地更改条件