Linq不会处理真正的查询 [英] Linq does't process true query
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问题描述
大家好，
我有一个方法，你可以看到，但它无法正常工作，因为这种风格返回0项。
我不确定但是与这段代码where子句可以是这样的（我给出一些示例参数）
Hi guys,
I have a method like as you can see but it does not work correctly because this style return 0 items.
I am not sure but with this code where clause can be like this(I give some example parameter)
where (Budget Between 130000 and 159999 or Budget Between 160000 and 20000) and (SanzimanTipi ='xxx' and SanzimanTipi ='xxx') and (YakitTuru ='xxx')
但是我ahave转换成这样的
but I ahave to Convert like this
where (Budget Between 130000 and 159999 or Budget Between 160000 and 20000) and (SanzimanTipi ='Otomatik' or SanzimanTipi ='Düz Vites') and (YakitTuru ='Dizel')
请给我一些回答
Please give me some answer
public List<CarEntity> GetSearchByKCriteria(int cityId, List<string> fuelType, List<string> gearType, List<string> budget,
List<string> caroser, List<string> enginePower)
{
Expression<Func<Car, bool>> query = null;
Expression<Func<Car, bool>> combine = null;
foreach (var bud in budget)
{
if (budget.Count >= 1)
{
if (bud == "1")
{
if (budget.Count > 1)
{
query = car => car.Budget >= 20000 && car.Budget <= 34999;
}
else
{
query = car => car.Budget >= 20000 && car.Budget <= 34999;
}
}
else if (bud == "2")
{
if (query != null)
{
combine = car => (car.Budget >= 35000 && car.Budget <= 49999);
query = query.Or(combine);
}
else
{
query = car => car.Budget >= 35000 && car.Budget <= 49999;
}
}
}
}
foreach (var caros in caroser)
{
if (caros != "-1" && !string.IsNullOrEmpty(caros))
{
if (query != null)
{
if (query.Expand().ToString().ToLower().Contains("karoser"))
{
combine = car => (car.Karoser == caros);
query = query.And(combine);
}
else
{
combine = car => car.Karoser == caros;
query = query.And(combine);
}
}
else
{
query = car => car.Karoser == caros;
}
}
}
foreach (var fuel in fuelType)
{
if (fuel != "-1" && !string.IsNullOrEmpty(fuel))
{
if (query != null)
{
if (query.Expand().ToString().ToLower().Contains("yakituru"))
{
combine = car => (car.YakitTuru==fuel);
query = query.Or(combine);
}
else
{
combine = car => car.YakitTuru == fuel;
query = query.And(combine);
}
}
else
{
query = car => car.YakitTuru == fuel;
}
}
}
foreach (var gear in gearType)
{
if (gear!="-1"&& !string.IsNullOrEmpty(gear))
{
if (query != null)
{
if (query.Expand().ToString().ToLower().Contains("sanzimantipi"))
{
combine = car => (car.SanzimanTipi == gear);
query = query.Or(combine);
}
else
{
combine = car => car.SanzimanTipi == gear;
query = query.And(combine);
}
}
else
{
query = car => car.SanzimanTipi == gear;
}
}
}
foreach (var engine in enginePower)
{
if (enginePower.Count >= 1)
{
if (engine == "1")
{
if (query != null)
{
if (query.Expand().ToString().ToLower().Contains("silindirhacmi"))
{
combine = car => (car.SilindirHacmi >= 0 && car.SilindirHacmi <= 1600);
query = query.Or(combine);
}
else
{
combine = car => (car.SilindirHacmi >= 0 && car.SilindirHacmi <= 1600);
query = query.And(combine);
}
}
else
{
query = car => car.SilindirHacmi >= 0 && car.SilindirHacmi <= 1600;
}
}
if (engine == "3")
{
if (query != null)
{
if (query.Expand().ToString().ToLower().Contains("silindirhacmi"))
{
combine = car => (car.SilindirHacmi >= 1601 && car.SilindirHacmi <= 1800);
query = query.Or(combine);
}
else
{
combine = car => (car.SilindirHacmi >= 1601 && car.SilindirHacmi <= 1800);
query = query.And(combine);
}
}
else
{
query = car => car.SilindirHacmi >= 1601 && car.SilindirHacmi <= 1800;
}
}
}
using (var context = DataContextFactory.CreateContext())
{
var result = (from fkCar in context.Car.Where(query)
join pkCarBrand in context.CarBrand on fkCar.Marka equals pkCarBrand.ID
where fkCar.IsActive == true
select new
{
entity = fkCar,
joinEntity = pkCarBrand
});
List<CarEntity> theCarList = new List<CarEntity>();
foreach (var item in result)
{
CarEntity theEntity = Mapper.Map(item.entity);
theEntity.CarBrand = Mapper.Map(item.joinEntity);
theCarList.Add(theEntity);
}
return theCarList;
}
}
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