Linq 转成 DataTable

public DataTable LinqToDataTable<T>(IEnumerable<T> varlist)
        {
             DataTable dtReturn = new DataTable();

             // column names 
             PropertyInfo[] oProps = null;
             if (varlist == null) return dtReturn;

             foreach (T rec in varlist)
             {
                  // Use reflection to get property names, to create table, Only first time, others 
                  if (oProps == null)
                  {
                       oProps = ((Type)rec.GetType()).GetProperties();
                       foreach (PropertyInfo pi in oProps)
                       {
                            Type colType = pi.PropertyType;

                            if ((colType.IsGenericType) && (colType.GetGenericTypeDefinition()      
                            ==typeof(Nullable<>)))
                             {
                                 colType = colType.GetGenericArguments()[0];
                             }

                            dtReturn.Columns.Add(new DataColumn(pi.Name, colType));
                       }
                  }

                  DataRow dr = dtReturn.NewRow();

                  foreach (PropertyInfo pi in oProps)
                  {
                       dr[pi.Name] = pi.GetValue(rec, null) == null ?DBNull.Value :pi.GetValue
                       (rec,null);
                  }

                  dtReturn.Rows.Add(dr);
             }
             return dtReturn;
        }