Problem with text field in datagrid when the number of rows exceeds the datagrid size

1. MVVM: Single datagrid row selection when a datagrid contains another datagrid in side RowDetailsTemplate

2. Datagrid current row number is the same as the dataset row number?

I'm working on a Window based application. I have 2 textboxes and a datagrid
on a form. The textboxes are databind to the same datasource as datagrid. I
want to use the following to update the dataset but I am not suer if the
datagrid's current row number does corresponds to the row number in the
dataset table that I want to update. Appreciate it if someone can give me
answer to this.
Thanks, Alpha

private void txtLastOdometer_Validated(object sender, System.EventArgs e)

dsMaintDued.Tables["MaintenanceDued"].Rows[dgMaintDued.CurrentRowIndex]["LastOdometerReading"] = txtLastOdometer.Text.ToString();

private void dtpLastService_Validated(object sender, System.EventArgs e)

dsMaintDued.Tables["MaintenanceDued"].Rows[dgMaintDued.CurrentRowIndex]["LastOdometerDate"] = dtpLastService.Value.ToString();

3. Need to add serveral large text fields that will exceed the 8k row size limit

4. maximum row size exceeds the maximum number of bytes per row (8060

5. How to set the DataGrid Row Size to a fixed size.

6. Datagrid column size and row size

7. [Datagrid,web form]: How the get the correct row values after sorting datagrid by header

8. How does a nested datagrid reference parent row in master datagrid?

9. DataGrid - Perform FullRowSelect without using Parent Row - Can Add Pic on Datagrid

10. Datagrid : Adding new rows to the Datagrid

11. read row values from datagrid and populate in new datagrid values from connected

12. Referencing Datagrid Rows while Datagrid is Sorted

13. How to Embedded one Window Form datagrid as row of other datagrid