public QueryFilter()

public async Task SearchingATable()
{
  try
  {
    await ArcGIS.Desktop.Framework.Threading.Tasks.QueuedTask.Run(() =>
    {
      using (Geodatabase geodatabase = new Geodatabase(new DatabaseConnectionFile(new Uri("path\\to\\sde\\file\\sdefile.sde"))))
      using (Table table = geodatabase.OpenDataset<Table>("EmployeeInfo"))
      {

        QueryFilter queryFilter = new QueryFilter
        {
          WhereClause = "COSTCTRN = 'Information Technology'",
          SubFields = "KNOWNAS, OFFICE, LOCATION",
          PostfixClause = "ORDER BY OFFICE"
        };

        using (RowCursor rowCursor = table.Search(queryFilter, false))
        {
          while (rowCursor.MoveNext())
          {
            using (Row row = rowCursor.Current)
            {
              string location = Convert.ToString(row["LOCATION"]);
              string knownAs = Convert.ToString(row["KNOWNAS"]);
            }
          }
        }
      }
    });
  }
  catch (GeodatabaseFieldException fieldException)
  {
    // One of the fields in the where clause might not exist. There are multiple ways this can be handled:
    // Handle error appropriately
  }
  catch (Exception exception)
  {
    // logger.Error(exception.Message);
  }
}

using (Geodatabase geodatabase = new Geodatabase(new DatabaseConnectionFile(new Uri("path\\to\\sde\\file\\sdefile.sde"))))
using (Table table = geodatabase.OpenDataset<Table>("TableWithChineseCharacters"))
{
  // This will fail with many database systems that expect Latin characters by default
  string incorrectWhereClause = "颜色 = '绿'";

  // Correct solution is to prepend the 'National String Prefix' to the attribute value
  // For example, with SQL Server this value is 'N'
  // This value is obtained using the SQLSyntax class
  string nationalStringPrefix = "";
  SQLSyntax sqlSyntax = geodatabase.GetSQLSyntax();
  nationalStringPrefix = sqlSyntax.GetSupportedStrings(SQLStringType.NationalStringPrefix).First();

  // This Where clause will work
  QueryFilter queryFilter = new QueryFilter()
  {
    WhereClause = "颜色 = " + nationalStringPrefix + "'绿'"
  };
}

public RowCursor SearchingATable(Table table, IReadOnlyList<long> objectIDs)
{
  QueryFilter queryFilter = new QueryFilter()
  {
    ObjectIDs = objectIDs
  };

  return table.Search(queryFilter);
}

// usage :   using (var row = FetchRowFromElement(...))
public static Row FetchRowFromElement(UtilityNetwork utilityNetwork, Element element)
{
  // Get the table from the element
  using (Table table = utilityNetwork.GetTable(element.NetworkSource))
  {
    // Create a query filter to fetch the appropriate row
    QueryFilter queryFilter = new QueryFilter()
    {
      ObjectIDs = new List<long>() { element.ObjectID }
    };

    // Fetch and return the row
    using (RowCursor rowCursor = table.Search(queryFilter))
    {
      if (rowCursor.MoveNext())
      {
        return rowCursor.Current;
      }
      return null;
    }
  }
}