What is e.RowIndex and e.EditIndex in Gridview?

Answer:

Basically e.RowIndex is used in Row_Deleting Event as well as Row_Command Event to find control ID within Gridview
whereas
e.EditIndex is ONLY used in Row_Updating Event to find control ID within Gridview.

In short,we can say that e.RowIndex is used in ITEMTEMPLATE whereas e.EditIndex is used in EDITITEMTEMPLATE.

For Ex:-

Inside Row_Command or Row_Deleting Event we can write:-

protected void grid_project_details_RowDeleting(object sender,GridViewDeleteEventArgs e)

{

  try

  {

     Label lbl_project_id = grid_project_details.Rows[e.RowIndex].FindControl("lbl_project_id") as Label;

  }

  catch(Exception ex)

  {

    throw ex;

  }

}

Same code,we can write inside Row Command event as :-

protected void grid_project_details_RowCommand(object sender,GridViewCommandEventArgs e)

{

   try

  {

     Label lbl_project_id = grid_project_details.Rows[e.RowIndex].FindControl("lbl_project_id") as Label;

  }

  catch(Exception ex)

  {

    throw ex;

  }

}

Inside Row_Updating Event we can write:-

protected void grid_project_details_RowUpdating(object sender,GridViewUpdateEventArgs e)

{

   try

   {

      Label lbl_project_id = grid_project_details.Rows[e.EditIndex].FindControl("lbl_project_id") as Label;

   }

   catch(Exception ex)

   {

      throw ex;

   }

}