CODEWITHSUNDEEP
c#
Bienvenido Omosura
Bienvenido Omosura

Reputation: 127

Deleting a row from a Datatable if that row exists in another Datable

I have two DataTables with the same columns:

DataTable dt;

DataTable posTable;

Sometimes they can have different numbers of row..

I want to delete a row from the table if it exists in another..

I tried using this code:

dt = dt.AsEnumerable().Zip<DataRow, DataRow, DataRow>(posTable.AsEnumerable(), (DataRow modif, DataRow orig) =>
{
  if (orig.ItemArray.SequenceEqual<object>(modif.ItemArray))
  {
     modif.Delete();
  }
  return modif;
}).CopyToDataTable<DataRow>();
dt.AcceptChanges();

but it didn't work :( [it only deletes what's not exists in another] i tried turning it around but gives me errors.

Any code suggestion?

Upvotes: 0

Views: 2371

Answers (2)

Tim Schmelter
Tim Schmelter

Reputation: 460228

Yes, you can use SequenceEqual but you have to use Remove instead of Delete. The latter deletes them from database if you use a DataAdapter, the former removes them from the table.

Another approach is filtering with LINQ and using CopyToDataTable on the remaining rows:

var rows1 = dt.AsEnumerable();
var rows2 = posTable.AsEnumerable();
dt = rows1 
    .Where(r1 => !rows2.Any(r2 => r1.ItemArray.SequenceEqual(r2.ItemArray)))
    .CopyToDataTable();

This keeps only non-duplicate rows because of the !rows2.Any in the Where-filter.

Upvotes: 1

Harsh Nag
Harsh Nag

Reputation: 84

This link also examples about Compare two tables

http://www.codeproject.com/Questions/686406/How-To-Compare-and-delete-datatable-row-using-Csha

Or

I think this example is use for you..

DataTable dt1 = new DataTable();
dt1.Columns.Add("Name");
dt1.Rows.Add("Apple");
dt1.Rows.Add("Banana");
dt1.Rows.Add("Orange");

DataTable dt2 = new DataTable();
dt2.Columns.Add("Name");
dt2.Rows.Add("Apple");
dt2.Rows.Add("Banana");

List<DataRow> rows_to_remove = new List<DataRow>();
foreach (DataRow row1 in dt1.Rows)
{
    foreach (DataRow row2 in dt2.Rows)
    {
        if (row1["Name"].ToString() == row2["Name"].ToString())
        {
            rows_to_remove.Add(row1);
        }
    }
}

foreach (DataRow row in rows_to_remove)
{
    dt1.Rows.Remove(row);
    dt1.AcceptChanges();
}

Upvotes: 1

Related Questions