Which way is the best for removing duplicates from a dataTable with multiple columns
<p>Which way is the best for removing duplicates from a dataTable for multiple columns?I mean below code is only for a single column.</p>

<pre><code>public 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;
}
</code></pre>

<p>I tried using string[] colName. It throws error at <code>dTable.Rows.Remove(dRow);</code></p>

<p>Please suggest.</p>
