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c#stored-proceduresdatatableasp.net-coredataset

Replacement for DataTable/DataSet in .NET Core (NET Standard 2.1)


.NET Core 3.1 supports DataTable/DataSet, DataRow, DataView, etc - which was not available when the OP created the following question

based on my research, it seems like .net core does not support DataTable/DataSet. I recently shifted to .net core for developing a new application, but failed to recognize that .net core does not have library for those in the first place. I used to use dt/ds for fetching the data via stored procedure and fill collection of classes. But now, I am quite lost with this new problem that I have to find replacement for dt/ds. To be more specific, I used to do this:

I have a stored procedure that takes four input parameters and returns a table.

ALTER PROCEDURE stp_Student

@Name nvarchar(450), 
@StudentIds tvp_ArrayInt READONLY,  
@StartDate date,
@EndDate date, 

AS

blah blah 

//returns student summary
SELECT  stu.StudentId, 
        stu.StudentName, 
        CASE WHEN (COUNT(DISTINCT course.Id) IS NOT NULL) THEN COUNT(DISTINCT course.Id) ELSE 0 END AS CourseCount, 
        CASE WHEN (SUM(course.TotalCourses) IS NOT NULL) THEN SUM(course.TotalCourses) ELSE 0 END AS TotalCourses, 
        CASE WHEN (SUM(course.Hours) IS NOT NULL) THEN SUM(course.Hours) ELSE 0 END AS Hours
FROM    #TempStudent AS #Temp 

and create a class with same fields as I have in my stored procedure.

public class StudentModel
{  
    public string StudentId { get; set; }
    public string StudentName { get; set; }
    public int CourseCount { get; set; }
    [Column(TypeName = "Money")]
    public decimal TotalCourses { get; set; }
    public double Hours { get; set; }
}

and fetch data and fill collection of class

using (SqlConnection conn = new SqlConnection(connectionString)) 
{
    SqlCommand cmd = new SqlCommand("sp_Student", conn);
    cmd.CommandType = CommandType.StoredProcedure;
    cmd.Parameters.AddWithValue("@Name", name);
    cmd.Parameters.AddWithValue("@StudentIds", studentIds);
    cmd.Parameters.AddWithValue("@StartDate", startDate);
    cmd.Parameters.AddWithValue("@EndDate", endDate);
    conn.Open();

    SqlDataAdapter da = new SqlDataAdapter();
    da.SelectCommand = cmd;
    da.Fill(ds);
    conn.Close();
}

foreach (Datarow row in ds.Tables[0].Rows)
{
    var model = new StudentModel();
    model.StudentId = Convert.ToString(row["StudentId"]);
    //etc..
    studentList.Add(model);
}

My bad, I should have researched more before I initiated the project, but I really need anyone's help to find replacement for the above code. Would it be possible to use .net core's FromSql method as a replacement? Any suggestion or sample codes would be appreciated.

Edit

According to Peter's article, found a way to implement ds/dt in .net core version, but having a bit problem passing an int array(StudentIds) to my stored procedure.

public List<StudentModel> GetStudents(string name, IEnumerable<int> studentIds, DateTime startDate, DateTime endDate)
    {
        List<StudentModel> students = new List<StudentModel>();
        StudentModel = null;

        List<DbParameter> parameterList = new List<DbParameter>();

        parameterList.Add(base.GetParameter("Name", name));
        parameterList.Add(base.GetParameter("StudentIds", studentIds));           
        parameterList.Add(base.GetParameter("StartDate", startDate));
        parameterList.Add(base.GetParameter("EndDate", endDate));       

        using (DbDataReader dataReader = base.ExecuteReader("stp_Student", parameterList, CommandType.StoredProcedure))
        {
            if (dataReader != null)
            {
                while (dataReader.Read())
                {
                    model = new StudentModel();
                    model.StudentId= (int)dataReader["StudentId"];
                    ....

                    students .Add(model);
                }
            }
        }
        return students;
    }
}

I think the problem comes from passing IEnumerable? How can I pass an int array to stored procedure correctly?


Solution

  • I don't know much about .Net Core, but I think you can use IEnumerable<SqlDataRecord> instead.