Question

I need the gridview to be displayed based on the dropdownlist : LastestTransactionFirst, EarlierTransactionFirst. So basically it’s desc or asc based on the date in gridview. May i know how should i go about it ?

This is my code for gridview selection. But I had a dropdownlist and need the gridview to appear based on the dropdownlist selection.

    myConnection.ConnectionString = strConnectionString;
    SqlCommand cmd = new SqlCommand("SELECT thDate, thType, thAmountIn, thAmountOut from [Transaction] ORDER BY thDate, thType, thAmountIn, thAmountOut DESC", myConnection);
    myConnection.Open();
    SqlDataReader reader1 = cmd.ExecuteReader();
    GridView1.DataSource = reader1;
    GridView1.DataBind();

Answer 1

This is an example of sorting in gridview

DataView dvItems = new DataView((DataTable)ds.Tables["datatable1"]);

 if (ddl_itemsorderby.SelectedValue == "MenuGroup")
     dvItems.Sort = "Menu_Group, Item_Name ASC";
 else if (ddl_itemsorderby.SelectedValue == "Item")
     dvItems.Sort = "Item_Name, Menu_Group ASC";
 else if (ddl_itemsorderby.SelectedValue == "Rate")
     dvItems.Sort = "Item_rate, Item_Name ASC";
 else if (ddl_itemsorderby.SelectedValue == "Quantity")
     dvItems.Sort = "Item_Quantity, Item_Name ASC";

 gridview1.DataSource = dvItems;
 gridview1.DataBind();

Here Menu_Group,Item_name … are the column names in the datatable which you bind to the gridview.

“Menu_Group, Item_Name ASC” This means that The forse order prority will be given to the Menu_Group first and second order priority will be given to Item_Name.
ASC is the Order type will be ascending

ddl_itemsorderby is the dropdownlist from which the column order will be selected.
dvitems is the dataview.

ASC is the ascending order.

You have to create a dataview containing the data in the datatable and then sort the values in the dataview and then bind the dataview to the gridview