如何查询linq lambda“where getdate（） - Ngaynhap＆lt; 15”

Question

我对该查询有疑问：

    select SanPham.*,TenSX  
    from SanPham join NhaSanXuat on SanPham.MaSX = NhaSanXuat.MaSX 
    where GETDATE()- NgayNhap < 15
    order by NgayNhap,MaSP desc

我似乎遇到了问题：where getdate() - Ngaynhap < 15

这是linq查询：

var sp = db.SanPhams.Join(db.NhaSanXuats, masp => masp.MaSX, mansx => mansx.MaSX, 
(masp, mansx) => new { SanPham = masp, NhaSanXuat = mansx })
.Where(ngaynhap=>DateTime.Now.Day - db.SanPhams.Select(n=>n.NgayNhap.Value.Day))
.OrderByDescending(nhap => nhap.SanPham.NgayNhap)
.ThenByDescending(masp => masp.SanPham.MaSP)
.Select(s => s.SanPham);

Answer 1

如果没有更多的信息，很难帮助你。但我认为您正在寻找以下内容：

var sp = db.SanPhams.Join(db.NhaSanXuats, masp => masp.MaSX, mansx => mansx.MaSX, 
(masp, mansx) => new { SanPham = masp, NhaSanXuat = mansx })
.Where(db => (DateTime.Now - db.SanPham.NgayNhap).Days < 15)
.OrderByDescending(nhap => nhap.SanPham.NgayNhap)
.ThenByDescending(masp => masp.SanPham.MaSP)
.Select(s => s.SanPham);