How to sort a dataset in ASP.NET C#-CodePudding

I am trying to sort a datatable into a DataSet. I want to sort by the Status Column in "DESC". But I am not aware how to go about this. I have tried the suggested solutions online but I seem not to be doing something right. Here is what I have tried, albeit, I have commented out the sorting lines of the code as they do not work for me. How can I sort my table using the Status column in Desc?

[WebMethod(EnableSession = true)]
public List < TaskListClass > getTasks() {
  var userId = Session["UserId"].ToString();
  List < TaskListClass > objB = new List < TaskListClass > ();
  try {
    using(var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["DBConnString"].ToString())) {
      connection.Open();
      DataSet Myds = new DataSet();
      // Myds.Tables[0].DefaultView.Sort = "Status desc";
     
      SqlDataAdapter sqldr = new SqlDataAdapter();
      string ProcName = "getTasks";
      SqlCommand cmd = new SqlCommand(ProcName, connection);
      cmd.CommandType = CommandType.StoredProcedure;
      cmd.Parameters.Add("@userId", SqlDbType.VarChar, 900).Value = userId;
      sqldr.SelectCommand = cmd;
      sqldr.Fill(Myds);
      DataTable dt = Myds.Tables[0];
      // DataTable dt = Myds.Tables[0].DefaultView.ToTable();

      for (int i = 0; i < dt.Rows.Count; i  ) {

        objB.Add(new TaskListClass() {
          Id = Convert.ToString(dt.Rows[i]["Id"]),
            Subject = Convert.ToString(dt.Rows[i]["Subject"]),
            Customer = Convert.ToString(dt.Rows[i]["Customer"]),
            Sender = Convert.ToString(dt.Rows[i]["Sender"]),
            Receiver = Convert.ToString(dt.Rows[i]["Receiver"]),
            Priority = Convert.ToString(dt.Rows[i]["Priority"]),
            StartDate = Convert.ToString(dt.Rows[i]["StartDate"]),
            EndDate = Convert.ToString(dt.Rows[i]["EndDate"]),
            Status = Convert.ToString(dt.Rows[i]["Status"]),
            OnProgress = Convert.ToString(dt.Rows[i]["OnProgress"]),
        });
      }
    }
  } catch (Exception e) {
    msg = e.ToString();
  }
  return objB;
}

CodePudding user response：

The way the current code is written, you could add this after the for-loop:

objB = objB.OrderByDescending(t => t.Status);

Depending of the datatype of Status, it might be sorted alphabetically.

CodePudding user response：

Ok, a few things.

first up, a dataset is a collection of tables - "many tables" possible.

But you have ONE table, so why use a dataset? I see no need. Just use a single data table for this.

And this will reduce the code.

So, I suggest this, or close to this:

using (var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["DBConnString"].ToString()))
    {
        using (var cmd = new SqlCommand("getTasks", connection))
        {
            connection.Open();
            cmd.CommandType = CommandType.StoredProcedure;
            DataTable dt = new DataTable();
            cmd.Parameters.Add("@userId", SqlDbType.VarChar).Value = userId;
            dt.Load(cmd.ExecuteReader());

            // now sort the datatable
            dt.DefaultView.Sort = "Status DESC";

            // now fill out our object with each row
            foreach (DataRow OneRow in dt.Rows)
            {
                objB.Add(new TaskListClass()
                {
                    Id = OneRow["Id"].ToString(),
                    Subject = OneRow["Subject"].ToString(),
                    Customer = OneRow["Customer"].ToString(),
                    Sender = OneRow["Sender"].ToString(),
                    Receiver = OneRow["Receiver"].ToString(),
                    Priority = OneRow["Priority"].ToString(),
                    StartDate = OneRow["StartDate"].ToString(),
                    EndDate = OneRow["EndDate"].ToString(),
                    Status = OneRow["Status"].ToString(),
                    OnProgress = OneRow["OnProgress"].ToString(),
                }); ;
            }
        }
    }
}
return objB;

CodePudding user response：

var dataRow = dt.AsEnumerable().OrderByDescending(x => x.Field("name")).ToList();
foreach (var item in dataRow)
{
//Enter your Code Here
}