Question

I want to create a data table when the aspx page is first loaded. I have placed my code to create the data table with a blank row in a class file. Below is the code for creating the data table.

public class PaymentDetailsDataTable
{
    public PaymentDetailsDataTable()
    {
        DataTable pventries = new DataTable();

        DataColumn col1 = new DataColumn("col1");
        DataColumn col2 = new DataColumn("col2");
        DataColumn col3 = new DataColumn("col3");
        DataColumn col4 = new DataColumn("col4");
        DataColumn col5 = new DataColumn("col5");
        DataColumn col6 = new DataColumn("col6");
        DataColumn col7 = new DataColumn("col7");
        DataColumn col8 = new DataColumn("col8");
        DataColumn col9 = new DataColumn("col9");

        col1.DataType = System.Type.GetType("System.Int32");
        col2.DataType = System.Type.GetType("System.String");
        col3.DataType = System.Type.GetType("System.String");
        col4.DataType = System.Type.GetType("System.String");
        col5.DataType = System.Type.GetType("System.String");
        col6.DataType = System.Type.GetType("System.String");
        col7.DataType = System.Type.GetType("System.String");
        col8.DataType = System.Type.GetType("System.Double");
        col9.DataType = System.Type.GetType("System.String");

        pventries.Columns.Add(col1);
        pventries.Columns.Add(col2);
        pventries.Columns.Add(col3);
        pventries.Columns.Add(col4);
        pventries.Columns.Add(col5);
        pventries.Columns.Add(col6);
        pventries.Columns.Add(col7);
        pventries.Columns.Add(col8);
        pventries.Columns.Add(col9);

        pventries.Rows.Add();        

    }
} 

In my code behind file, I have instantiated my class and tried to use it as follows as follows:

    public partial class create_pv  : System.Web.UI.Page 
{
    String conn = WebConfigurationManager.ConnectionStrings["pvconn"].ToString();

    PaymentDetailsDataTable pmd = new PaymentDetailsDataTable();




    protected void Page_Load(object sender, EventArgs e)
    {


        /**/if(!IsPostBack)
            pmd.PaymentDetailsDataTable(); 
            allpventries.DataSource = pmd;
            allpventries.DataBind();
        }
}

Now when I try to access the method PaymentDetailsDataTable like this pmd.PaymentDetailsDataTable() I get the following error

'PaymentDetailsDataTable' does not contain a definition for 'PaymentDetailsDataTable' and no extension method 'PaymentDetailsDataTable' accepting a first argument of type 'PaymentDetailsDataTable' could be found (are you missing a using directive or an assembly reference?)  

If I change my method return type(PaymentDetailsDataTable) to void it works but I later want to bind the data table to a grid view(called allpventries) and it brings a compiler error.

How may I achieve binding a datagrid from a datatable whose code base is in a different class? Later I will be adding new rows to the datatable. Alternative options also acceptable to achieve this.

Very new in object oriented programming and C# ASP.NET.

Answer 1

The class PaymentDetailsDataTable should be a sub-class of DataTable or define a method in PaymentDetailsDataTable class which returns reference of DataTable object.

public class PaymentDetailsDataTable : DataTable
{
    public PaymentDetailsDataTable()
    {
        Columns.Add("Col1", typeof(int));
        Columns.Add("Col2");

        Rows.Add(1, "Foo");
        Rows.Add(2, "Bar");
    }
}

and code in page_load handler,

protected void Page_Load(object sender, EventArgs e)
{
  if(!IsPostBack)
   {
      allpventries.DataSource = new PaymentDetailsDataTable();
      allpventries.DataBind();
   }
}