如何在Linq连接后获取“剩余”记录

var leftTable = new List<int>() { 1, 2, 3, 4, 5 };
var rightTable = new List<int>() { 4, 5, 6, 7, 8 };

var leftOuterJoinQuery = from leftRecord in leftTable
                         join rightRecord in rightTable on leftRecord equals rightRecord into matchedRecords
                         from record in matchedRecords.DefaultIfEmpty()
                         where record == null
                         select leftRecord;

foreach (var record in leftOuterJoinQuery)
{
    Console.WriteLine(record);
}