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Lets say I have a datatable dt (it contains advertisers) and I want to remove a row from dt where the advertiserID equals a value, how do I do that?

DataTable dt = new DataTable();
//populate the table
dt = DynamicCache.GetAdvertisers();

//I can select a datarow like this:
DataRow[] advRow = dt.Select("advertiserID = " + AdvID);

//how do you remove it, this get's me an error
dt.Rows.Remove(advRow)

so how do you do it correctly?

Thanks.

flavour404
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1 Answers1

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advRow is an ARRAY. You have to identify which row in the array to delete.

dt.Rows.Remove(advRow[0]);

of course, this only removes it from the datatable, not necessarily the data source behind it (sql, xml, ...). That will require more...

and it would be a good idea to check the array or iterate the array after the select...

var datatable = new DataTable();
            DataRow[] advRow = datatable.Select("id=1");
            datatable.Rows.Remove(advRow[0]);
            //of course if there is nothing in your array this will get you an error..

            foreach (DataRow dr in advRow)
            {
                // this is not a good way either, removing an
                //item while iterating through the collection 
                //can cause problems.
            }

            //the best way is:
            for (int i = advRow.Length - 1; i >= 0; i--)
            {
                datatable.Rows.Remove(advRow[i]);
            }
            //then with a dataset you need to accept changes
            //(depending on your update strategy..)
            datatable.AcceptChanges();
Cos Callis
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  • Ah, that was exactly the piece of information that I was missing - thanks great. Do you need to do dt.acceptchanges after? – flavour404 Apr 27 '11 at 22:47
  • @flavour404, Depending on your update strategy, yes... at some point you will need to do an `.AcceptChanges();` (see the extended sample I added...) – Cos Callis Apr 27 '11 at 22:51
  • Thanks Cos, that was awesome advice. – flavour404 May 03 '11 at 19:03
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    The .AcceptChanges() works only on rows what exists in the table! After .Delete() the row still exist (as DataRowState.Deleted) but not after .Remove()! So .AcceptChanges() is not necessary in this sit. – Jettero Jul 17 '15 at 11:18