从Linq查询调用方法 [英] Call Method from Linq query

问题描述

我使用LINQ查询和呼叫方法如..

  oPwd = objDecryptor.DecryptIt（（c.Password.ToString （））
  

将返回空值。

表示，这将无法正常工作。

我是如何解决这个问题。

谢谢..

 在db.User 
变种q = 
从我们携手℃的db.EmailAccount上s.UserId等于C .UserId 
在db.POPSettings 
 JOIN D上c.PopSettingId等于d.POPSettingsId 
，其中s.UserId ==用户用户名与放大器;&安培; c.EmailId == EMAILID 
选择新的
 {
 oUserId = s.UserId，
 oUserName = s.Name，
 oEmailId = c.EmailId，
 oEmailAccId = c.EmailAccId，
 oPwd = objDecryptor.DecryptIt（c.Password.ToString（）），
 oServerName = d.ServerName，
 oServerAdd = d.ServerAddress，
 oPOPSettingId = d.POPSettingsId，
} ; 
  

解决方案

如果是LINQ到SQL或实体框架。你需要把它分解成步骤（因为它无法执行，在DB）。例如：

 变种Q =从s在db.User 
将C在db.EmailAccount上s.UserId等于c.UserId 
在c.PopSettingId db.POPSettings JOIN D等于d.POPSettingsId 
，其中s.UserId ==用户用户名与放大器;&安培; c.EmailId == EMAILID 
选择新的
 {
 oUserId = s.UserId，
 oUserName = s.Name，
 oEmailId = c.EmailId，
 oEmailAccId = c.EmailAccId，
 oPwd = c.Password，
 oServerName = d.ServerName，
 oServerAdd = d.ServerAddress，
 oPOPSettingId = d.POPSettingsId，
}; 
  

然后用 AsEnumerable（）突破组成对后端存储：

  VAR QUERY2 =从行q.AsEnumerable（）
选择新
 {
 row.oUserId，
 row.oUserName，
 row.oEmailId，
 row.oEmailAccId，
 oPwd = objDecryptor.DecryptIt（row.oPwd ），
 row.oServerName，
 row.oServerAdd，
 row.oPOPSettingId 
}; 
  

I am using Linq query and call method Like..

oPwd = objDecryptor.DecryptIt((c.Password.ToString())

it will return null value.

Means this will not working.

how I Resolve this.

Thanks..

var q =
    from s in db.User
    join c in db.EmailAccount on s.UserId equals c.UserId
    join d in db.POPSettings 
        on c.PopSettingId equals d.POPSettingsId
    where s.UserId == UserId && c.EmailId == EmailId
    select new
    {
        oUserId = s.UserId,
        oUserName = s.Name,
        oEmailId = c.EmailId,
        oEmailAccId = c.EmailAccId,
        oPwd = objDecryptor.DecryptIt(c.Password.ToString()),
        oServerName = d.ServerName,
        oServerAdd = d.ServerAddress,
        oPOPSettingId = d.POPSettingsId,
    };

解决方案

If that is LINQ-to-SQL or Entity Framework. You'll need to break it into steps (as it can't execute that at the DB). For example:

var q = from s in db.User
        join c in db.EmailAccount on s.UserId equals c.UserId
        join d in db.POPSettings on c.PopSettingId equals d.POPSettingsId
        where s.UserId == UserId && c.EmailId == EmailId
        select new
        {
            oUserId = s.UserId,
            oUserName = s.Name,
            oEmailId = c.EmailId,
            oEmailAccId = c.EmailAccId,
            oPwd = c.Password,
            oServerName = d.ServerName,
            oServerAdd = d.ServerAddress,
            oPOPSettingId = d.POPSettingsId,
        };

then use AsEnumerable() to break "composition" against the back-end store:

var query2 = from row in q.AsEnumerable()
        select new
        {
            row.oUserId,
            row.oUserName,
            row.oEmailId,
            row.oEmailAccId,
            oPwd = objDecryptor.DecryptIt(row.oPwd),
            row.oServerName,
            row.oServerAdd,
            row.oPOPSettingId
        };

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