allow sorting by column gridview

Question

I am writing project which gets data from Data Acess Layer and show it in GridView. The problem is to allow sorting by column. When I click on head of columnt following occu

Answer 1

The GridView does not sort itself. You need to add some code for a GridView sorting event and wire it up.

First, you add the name of the OnSorting event to the GridView on the .aspx page:

<asp:GridView ID="gridView" OnSorting="gridView_Sorting" runat="server" />

Then, you add that event in the code-behind. This example also handles changing the sort direction -- once the user has sorted, they may want to reverse the sort direction, and you have to keep track of that.

   private string ConvertSortDirectionToSql(SortDirection sortDirection)
    {
       string newSortDirection = String.Empty;

   switch (sortDirection)
   {
      case SortDirection.Ascending:
             newSortDirection = "ASC";
             break;

      case SortDirection.Descending:
         newSortDirection = "DESC";
         break;
   }

   return newSortDirection;
}

protected void gridView_Sorting(object sender, GridViewSortEventArgs e)
{
   DataTable dataTable = gridView.DataSource as DataTable;

   if (dataTable != null)
   {
      DataView dataView = new DataView(dataTable);
      dataView.Sort = e.SortExpression + " " + ConvertSortDirectionToSql(e.SortDirection);

      gridView.DataSource = dataView;
      gridView.DataBind();
   }
}

Answer 2

You need to define a sort melhod, and implement it:

<asp:GridView ID="GridView1" **OnSorting="gridViewSorting"** runat="server" />



protected void gridViewSorting(object sender, GridViewSortEventArgs e)
{
   DataTable dataTable = gridView.DataSource as DataTable;

   if (dataTable != null)
   {
      DataView dataView = new DataView(dataTable);
      dataView.Sort = your sort expression

      gridView.DataSource = dataView;
      gridView.DataBind();
   }
}