使用多个IEnumerable联接

问题描述

如果我有3张桌子。如何使用IEnumerable LINQ Joins将所有3个表连接在一起？这是我当前的查询，我想使用GPRow id = Budgettargets id加入另一个名为BudgetTargets的IEnumerable

var rows = _context.GpRows.Join(
            _context.ShopInfos,GpRow => GpRow.ShopId,ShopInfo => ShopInfo.ShopId,(GpRow,ShopInfo) => new{ 
                ShopName = ShopInfo.ShopName,State = ShopInfo.State,YearMonth = String.Concat(GpRow.Year,GpRow.Month),GpRow.Year,GpRow.Month,GpRow.Id,GpRow.ShopId,GpRow.PaintSale,GpRow.PanelSale,GpRow.PartsSale,GpRow.OtherSale,GpRow.PaintCost,GpRow.PanelCost,GpRow.PartsCost,GpRow.OtherCost,GpRow.PanelWages,GpRow.PaintWages,GpRow.Depreciation,GpRow.ForecastedSales,GpRow.Expenses
            }
        )
        .Where(GpRow => shopId_Array.Contains(GpRow.ShopId))
        .OrderByDescending(a => a.Year).OrderByDescending(b => b.Month).ThenBy(c => c.State).ThenBy(c => c.ShopName)
        .ToList();

解决方法

我同意@juharr的评论。 LINQ查询格式的目的有时比流利的API风格更清楚。这是查询的编写方式。

var rows = from GpRow in _context.GpRows
    join ShopInfo in _context.ShopInfos on GpRow.ShopId equals ShopInfo.ShopId
    orderby GpRow.ShopId descending,GpRow.Month descending,ShopInfo.State,ShopInfo.ShopName
    select new { 
        ShopName = ShopInfo.ShopName,State = ShopInfo.State,YearMonth = String.Concat(GpRow.Year,GpRow.Month),GpRow.Year,GpRow.Month,GpRow.Id,GpRow.ShopId,GpRow.PaintSale,GpRow.PanelSale,GpRow.PartsSale,GpRow.OtherSale,GpRow.PaintCost,GpRow.PanelCost,GpRow.PartsCost,GpRow.OtherCost,GpRow.PanelWages,GpRow.PaintWages,GpRow.Depreciation,GpRow.ForecastedSales,GpRow.Expenses
    };