C#

var cfToggleList = (from cf in QCHelperall
        join toggle in ToggleDataAll
          on new { val = cf.Section.Trim().ToUpper(), 
          val1 = cf.Li.Trim().ToUpper(), 
          val2 = cf.Period.Replace("A", "").Replace("E", "").Trim().ToUpper(), 
          val3 = cf.Broker.Trim().ToUpper() }

          equals new { val = toggle.Section.Trim().ToUpper(), 
          val1 = toggle.Lineitem.Trim().ToUpper(), 
          val2 = toggle.Period.Trim().ToUpper(), 
          val3 = toggle.Broker.Trim().ToUpper() }

          into tempJoin
        from leftJoin in tempJoin.DefaultIfEmpty()
        select new QCHelper()
        {
            Broker = cf.Broker,
            BrokerName = (from brk in BrokerCodeName
                  where brk.BrokerCode.ToUpper() == cf.Broker.Split('-')[0].ToUpper()
                  select brk.BrokerName).FirstOrDefault(),
            Section = cf.Section,
            Li = cf.Li,
            StandardDate = cf.Period,
            Value = cf.Value,
            FycheckToggle = leftJoin == null ? string.Empty : (leftJoin.ToggleText.Contains("FYCHECKTOGGLE") ? leftJoin.ToggleText : string.Empty),
            QcCheckToggle = leftJoin == null ? string.Empty : (leftJoin.ToggleText.Contains("QCCHECKTOGGLE") ? leftJoin.ToggleText : string.Empty)
        }).ToList<QCHelper>();

BrokerName = (from brk in BrokerCodeName
          where brk.BrokerCode.ToUpper() == cf.Broker.Split('-')[0].ToUpper()
          select brk.BrokerName).FirstOrDefault(),

/// Thinking face 🤔
/// </summary>
 UnicodeString Thinking  =0x1f914;