Remove Duplicate Rows in Data Table

    public static DataTable RemoveDuplicateRows(DataTable dTable, string colName)

    {

        Hashtable hTable = new Hashtable();

        ArrayList duplicateList = new ArrayList();

 

        //Add list of all the unique item value to hashtable, which stores combination of key, value pair.

        //And add duplicate item value in arraylist.

        foreach (DataRow drow in dTable.Rows)

        {

            if (hTable.Contains(drow[colName]))

                duplicateList.Add(drow);

            else

                hTable.Add(drow[colName], string.Empty);

        }

 

        //Removing a list of duplicate items from datatable.

        foreach (DataRow dRow in duplicateList)

            dTable.Rows.Remove(dRow);

 

        //Datatable which contains unique records will be return as output.

        return dTable;

    }