Confusion of sql helper class

Question

I want to display list of names and roll no of students who are studying in nursery stored in my database......But there seems to be an error in following code which i can't figure out

 protected void NurseryButton_Click(object sender, EventArgs e)
{

    SQLHelper sqhlpr = new SQLHelper();
    sqhlpr.SqlText = "Select StudentName,RollNo from tblStudentInfo where Class=@Class";
    sqhlpr.AddParameter("Class", sender.ToString());
    sqhlpr.ExecuteScalar(false);
    DataTable dt = sqhlpr.getDataTable(false);
    Label1.Text = dt.Rows[0]["StudentName"].ToString();
}

The error goes like this"There is no row at position 0" in my last line of text i.e.in label1.text. Can anybody help me??

Answer 1

You have to use SqlHelper.ExecuteDataSet so get the result set of your query. ExecuteScalar resutns a single value from row. Example

DataTable dt = SqlHelper.ExecuteDataSet(ConnString,
                                 CommandType.Text,
                                 "Select StudentName,RollNo from tblStudentInfo where Class=@Class",
                                 parameter).Tables[0];