C# - Remove rows with the same column value from a DataTable

Question

I have a DataTable which looks like this:

 ID   Name    DateBirth
.......................
 1     aa      1.1.11
 2     bb      2.3.11
 2     cc          


        

Answer 1

I was solving the same situation and found it quite interesting and would like to share my finding.

1. If rows are to be distinct based on ALL COLUMNS.

DataTable newDatatable = dt.DefaultView.ToTable(true, "ID", "Name", "DateBirth");

The columns you mention here, only those will be returned back in newDatatable.

2. If distinct based on one column and column type is int then I would prefer LINQ query.

  DataTable newDatatable = dt.AsEnumerable()
                           .GroupBy(dr => dr.Field("ID"))
                           .Select(dg => dg).Take(1)
                           .CopyToDataTable();

3. If distinct based on one column and column type is string then I would prefer loop.

List toExclude = new List();
for (int i = 0; i < dt.Rows.Count; i++)
{
    var idValue = (string)dt.Rows[i]["ID"];
    if (toExclude.Contains(idValue))
    {
        dt.Rows.Remove(dt.Rows[i]);
        i--;
    }
    toExclude.Add(glAccount);
}

Third being my favorite.

I may have answered few things which are not asked in the question. It was done in good intent and with little excitement as well.

Hope it helps.