Question

I am a beginner and writing code to display data in a Gridview using Asp.Net and c#. I want to know if the approach I followed is correct or not. I want suggestions on standards and architectural issues, best practices with my code so that I can modify my code accordingly. I appreciate your great suggestions and code additions.

Connection Code:

    public class DemoProjConnectionClass
    {
        public SqlConnection DemoProjConnection()
        {
            SqlConnection con = new SqlConnection("Data Source=Localhost;Initial Catalog=master;Integrated Security=True");
            return con;
        }
    }

Domain Code(gets & sets):

public class DemoProjDomainClass
{

public int EmpId { get; set; } 
public string EmpName { get; set; } 
public int Salary { get; set; } 

 } 

Class Library Code:

public class DemoProjServiceClass
{
    public IList<DemoProjDomainClass> getDemoProjList()
    {
        string sqlDemoProjList;
        sqlDemoProjList = "SELECT EmpId,EmpName,Salary from Employee";
        DemoProjConnectionClass x = new DemoProjConnectionClass();
        SqlConnection con = x.DemoProjConnection();
        con.Open();
        SqlCommand cmd = new SqlCommand(sqlDemoProjList, con);
        cmd.CommandType = CommandType.Text;
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        DataSet ds = new DataSet();
        da.Fill(ds, "tempTable1");



        IList<DemoProjDomainClass> DemoProjList = new List<DemoProjDomainClass>();
        for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
        {
            DemoProjDomainClass _obj = new DemoProjDomainClass();

            _obj.EmpId = Convert.ToInt16(ds.Tables[0].Rows[i][0]);_obj.EmpName = ds.Tables[0].Rows[i][1].ToString();_obj.Salary = Convert.ToInt16(ds.Tables[0].Rows[i][2]);DemoProjList.Add(_obj);
        }
        return DemoProjList;
    }
} 

UI Code

protected void Page_Load(object sender, EventArgs e)
{
   DemoProjServiceClass ob=new DemoProjServiceClass();
    GridView1.DataSource = ob.getDemoProjList();
    GridView1.DataBind();

}

Answer 1

Connection Code:

I will not hardcode the connectionstring like that. I will keep that in a config file (web.config or so..) and read from there so that i can change my connection string any time if needed with a recompilation.

Class Library Code

Your getDemoProjList method dont have any exception handling. I will wrap that code with using statement so that i dont need to worry abour closing my connection

UI

I dont think you should load data in the PageLoad without checking whether it is a postback or not. So will use a isPostBAck property checkk. I would also do a null check before binding it as the data source of the grid.

protected void Page_Load(object sender, EventArgs e)
{
  if (!IsPostBack)
  {
    DemoProjServiceClass ob=new DemoProjServiceClass();
    List<DemoProjDomainClass> objList=ob.getDemoProjList();
    if(objList!=null)
    {
       GridView1.DataSource = objList;
       GridView1.DataBind();
    }
   }

}