C# ne命令并使用它执行两个sql语句，并使用sql data reader代替ReadNextResult（）方法来填充注释。您使用的是什么sql？如果您使用t-sql，答案将与您使用plsql时的答案不一样。这很好。我不知道该感谢您多少。我希望我能多投几次

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ne命令并使用它执行两个sql语句，并使用sql data reader代替ReadNextResult（）方法来填充注释。您使用的是什么sql？如果您使用t-sql，答案将与您使用plsql时的答案不一样。这很好。我不知道该感谢您多少。我希望我能多投几次票。。感谢您如此详细地解释这一点。我已经下载了linqpad，它帮了我很大的忙。我希望我能为我的项目雇用你。再次感谢

var a = from arow in context.post
where arow.post_id == id && arow.post_isdeleted == false
select new
{
     arow.post_id,
     PostComments = from c in context.comment
                    where c.CommentPostID == arow.post_id
                    select new
                    {
                        c.id,
                        c.title     
                    }
}


List<PostType> pt;
foreach (var s in a)
{
     pt = new PostType();
     pt.PostID = s.post_id;

     //how would I use ADO.NET to put this in a custom class?
     foreach(var ctl in s.PostComments)
     {
         ctl.Title = ctl.title;
         pt.CommentT.Add(ctl);
     }
     ptl.Add(pt);
}

-Select * from Posts where post_Id = id AND IsDeleted = 0;
-Select * from Postcomments where id = cid;

foreach(DataRow dr in PostsTable.Rows)
{
 //Fill the Post Custom class
 SecondTable.DefaultView.RowFilter = string.Format("PostID = {0}",dr["postID"]);
 foreach(DataRow r in SecondTable.Rows)
 {
  //Fill the Comments Custom class
 } 
}

SELECT 
    p.post_id
    c.id,
    c.title
FROM 
    post p 
WHERE 
    p.id == 'id' and 
    isdeleted = false
INNER JOIN comment c ON c.commentpostid = p.post_id

select post_id, id, title from postcomments pc
where post_id = @id and exists(
    select post_id form post p where p.post_id = pc.post_id and isdeleted = false
)

public class PostType
{
    public int PostId { get; set; }
    public List<PostComment> PostComments { get; set; }
}
public class PostComment
{
    public int CommentId { get; set; }
    public string Title { get; set; }
}

SELECT P.post_id, C.id, C.title 
FROM post As P, comment As C
WHERE
    P.post_id = @PostId
    AND P.post_isdeleted = 0  -- 0 is false
    AND C.CommentPostID = P.post_id

int postIdInput = 42; // desired post_id to search for

// PostType delcared prior to getting the results
PostType postType = new PostType()
{
    PostId = postIdInput,
    PostComments = new List<PostComment>()
};

 // Database interaction starts here...
 // updated SQL statement to use column name aliases for clarity when used by the SqlDataReader
 string sqlStatement = @"SELECT P.post_id As PostId, C.id As CommentId, C.title As Title
                         FROM post As P, comment As C
                         WHERE
                             P.post_id = @PostId
                             AND P.post_isdeleted = 0  -- 0 is false
                             AND C.CommentPostID = P.post_id";

 string sqlConnectionString = "..."; // whatever your connection is... probably identical to your L2S context.Connection.ConnectionString
 using (SqlConnection conn = new SqlConnection(sqlConnectionString))
 {
     conn.Open();
     SqlCommand command = new SqlCommand(sqlStatement, conn);
     command.Parameters.AddWithValue("@PostId", postIdInput); // use Parameters.Add() for greater specificity

    SqlDataReader reader = command.ExecuteReader();
    while (reader.Read())
    {
        // postId was set based on input, but could be set here as well although it would occur repeatedly
        // if desired, uncomment the 2 lines below and there's no need to initialize it earlier (it'll be overwritten anyway)
        //int postId = Int32.Parse(reader["PostId"].ToString());
        //postType.PostId = postId;
        int commentId = Int32.Parse(reader["CommentId"].ToString());
        string title = reader["Title"].ToString();

        // add new PostComment to the list
        PostComment postComment = new PostComment
        {
            CommentId = commentId,
            Title = title
        };
        postType.PostComments.Add(postComment);
    }

    // done! postType is populated...
}

// use postType...

var query = /* your L2S query here */;
string sqlStatement = context.GetCommand(query).CommandText;    // voila!

context.Log = Console.Out;

SELECT [t0].[post_id], [t1].[id], [t1].[title], (
 SELECT COUNT(*)
 FROM [comment] AS [t2]
 WHERE [t2].[id] = [t0].[post_id]
 ) As [value]
FROM [post] As [t0]
LEFT OUTER JOIN [comment] As [t1] ON [t1].[CommentPostID] = [t0].[post_id]
WHERE ([t0].[post_id] = @p0) AND ([t0].[post_isdeleted] = 0)
ORDER BY [t0].[post_id], [t1].[id]

SELECT [P].[post_id] As PostId, [C].[id] As CommentId, [C].[title] As Title--, (
-- SELECT COUNT(*)
-- FROM [comment] AS [t2]
-- WHERE [t2].[id] = [t0].[post_id]
-- ) As [value]
FROM [post] As [P]
LEFT OUTER JOIN [comment] As [C] ON [C].[CommentPostID] = [P].[post_id]
WHERE ([P].[post_id] = @PostId) AND ([P].[post_isdeleted] = 0)
--ORDER BY [t0].[post_id], [t1].[id]

var query = from arow in context.post
            from c in context.comment
            where arow.post_id == id && arow.post_isdeleted == false
                  && c.CommentPostID == arow.post_id
            select new
            {
                arow.post_id,
                c.id,
                c.title    
            };

SELECT [t0].[post_id], [t1].[id], [t1].[title]
FROM [post] As [t0], [comment] As [t1]
WHERE ([t0].[post_id] = @p0) AND ([t0].[post_isdeleted] = 0)
      AND ([t1].[CommentPostID] = [t0].[post_id])