PredicateBuilder返回所有用户谓词.或者

Question

我正在使用C#,Entity Framework Code First 4.4.0.0和.NET Framework 4.0开发一个库.

我有这个代码:

string[] keywords = null;
if (query_string != null)
    keywords = query_string.Split(' ');

// Check parameter. It will throw an exception.
ParameterCheck.CheckObjectId(user_id);

// Convert parameter to int.
int userId = Int32.Parse(user_id);

try
{
    using (var context = new AdnLineContext())
    {
        context.Configuration.ProxyCreationEnabled = false;

        //IQueryable<User> query = context.Users;
        IQueryable<User> query = context.Users.AsExpandable();
        var predicate = PredicateBuilder.False<User>();

        foreach (string keyword in keywords)
        {
            string temp = keyword;

            predicate = predicate.Or(u => u.Name.Contains(temp) ||
                                     u.State.Contains(temp) ||
                                     u.HashTags.Contains(temp));
        }
        query.Where(predicate);
        query.Include("WhoHasBlockedMe").Include("Friends");

        var users = query.ToList();

        [ ... ]
    }
}

如果keywords = {"john", "happy"}我想得到这个SQL:

select * from users where
users.name like '%john%' or 
users.state like '%john%' or 
users.hashtags like '%john%' or 
users.name like '%happy%' or 
users.state like '%happy%' or 
users.hashtags like '%happy%'; 

我怎么能用PredicateBuilder做到这一点？

顺便说一句,我从http://www.albahari.com/nutshell/predicatebuilder.aspx下载了LinqKit

更新
我已经添加了一个断点var users = query.ToList();并且query有这个SQL:

{SELECT 
[Extent1].[UserId] AS [UserId],
[...]
FROM [dbo].[Users] AS [Extent1]}

它没有Where条款.

Answer 1

你的问题在这里:

query.Where(predicate);
query.Include("WhoHasBlockedMe").Include("Friends");

var users = query.ToList();

.Where并且.Include不修改基础查询,它们返回一个新查询.

使用

query = query.Where(predicate);
query = query.Include("WhoHasBlockedMe").Include("Friends");

var users = query.ToList();

代替.