CurrentRowIndex after sorting

I need to get the value of a column in the current row of a DataGrid. The documentation warns, quite correctly, that the Datagrid could be sorted, so the order of rows is not necessarily the same as inh the underlying dataTable.

Iw there a solution to this problem

This was recently asked in another thread:
http://www.windowsforms.com/Forums/ShowPost.aspx tabIndex=1&tabId=41&PostID=12601

But the discussion appeared to turn more towards binding. In my case, the code goes something like:

  private ds as DataSet
  private dt as DataTable
  private withevents dg  as System.Windows.Forms.DataGrid
  ....
  dapp = new SqlDataAdapter( "select * from my_table", my_connection )
  dapp.fill( ds, "apps" ) ' name of table in memory will be "apps"
  dt = ds.tables("apps")
  dg = new System.Windows.Forms.DataGrid()
  dg.DataSource = ds.tables("apps")

There is also (unrelated) code which maskes the grid updateable. Then, I have a clicked event for a Drill-Down button, where I use:

  dim rdx as integer = dg.CurrentRowIndex
  dim sel_dr as DataRow = dt.rows( rdx )
  dim sel_app as String = sel_dr("app_code" )
  MsgBox( sel_app,, "Selected row number: " & rdx & "  zero-based" )

My test is:

- the grid displays two rows
- put the cursor on the second row
- sort the grid, in such a manner that the two rows change order
- click on the Drill button
It displays the wrong index and wrong data. It keeps doing so after sorting.
If I don't sort, then it is always correct.

Any thoughts
Can we somehow access the rows of the DataGrid as opposed to the rows of the DataTable

Andrew

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CurrentRowIndex after sorting

Scot Campbell
In Web Apps , there's no such class as a CurrencyManager.

A datasource (DataTable, DataSet, .....) does not know which row is currently displayed or active.
You'll have to work with the methods of the DataGrid or CurrencyManager.
darien_specter
You'll have to use the CurrencyManager that will be returned when you access the BindingContext of the form for your datatable.

CurrencyManager cm = (CurrencyManager)this.BindingContext[dt];

You can then use the position property of the CurrencyManager to get the index of the current row.
Benny Au-Young
thanks for your help. The following now works for me:

        dim c_cell as DataGridcell = dg.currentCell
        dim c_row as integer = c_cell.RowNumber
        dim c_col as integer = c_cell.ColumnNumber
        dim sel_str = dg( c_row, c_col)
        if IsDBnull( sel_str ) then
              sel_str = "isDbNull() = true"
        end if
        msgbox( sel_str, , "row: " & c_row & "  ,col: " & c_col & "    zero-based" )

The above is placed in the code for the DrillDown button, and is not being confused by any sorting which might have occured in between.
wrightti
I just realise there are TWO classes named DataGrid, although the solution to the problem is similar. I am developing a Windows application, not a Web one.

I will try using the items collection datagrid( row, col )
CurrentRowIndex after sorting

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