Linq，選擇值+ - 一個值

Question

我需要在產品表上進行選擇。 該產品有一個名爲郵編 我需要得到全部產品從特定郵政編碼列，比選擇郵編

所以，如果我有郵政編碼較高和較低的5郵編51235 我所需要的產品從5更高的郵政編碼和更低的郵政編碼，這可能與linq？

希望有人能幫助

Answer 1

要獲得郵政編碼-5和郵政編碼+ 5

container.Products.Where(w => (w.ZipCode > zipCode - 5) && (w.ZipCode < zipCode + 5)); 

之間的產品才能獲得產品都有各自郵編正好等於郵政編碼+/- 5和電流郵編。

container.Products.Where(w => (w.ZipCode == zipCode - 5) || (w.ZipCode == zipCode + 5) || (w.ZipCode == zipCode + 5)); 

Answer 2

也許是這樣的：

var zip = 51235; 
context.Products.Where(p => p.ZipCode >= zip - 5 && p.ZipCode <= zip +5); 

或者這樣：

var zip = 51235; 
var products = from p in context.Products 
where p.ZipCode >= zip -5 && p.ZipCode <= zip + 5 
select p; 

UPDATE：

如果你想要做的這一切，你可以做這樣一個說法這個：

 var products = Products.Where(p1 => 
       Products.Select(p2 => p2.ZipCode) 
         .Distinct() 
         .Where(p3 => p3 >= zipCode) 
         .Take(4) 
         .Union(
          Products.Select(p4 => p4.ZipCode) 
          .Distinct() 
          .Where(p5 => p5 < zipCode) 
          .Take(3) 
         ).Contains(p1.ZipCode) 
       ); 

但是，將它拆分爲不同的語句可能會更容易，以使其更易讀。

Answer 3

可以使用，

var collectionEqualToZipCode = SourceCollection.Where(source=> source.Zip == SelectedZip); 

int lessZipCodesTaken = 0; 
int greaterZipCodesCountTaken = 0; 
var collectionlessthanOrGreaterthanZipCode = SourceCollection.TakeWhile(source => 
(source.Zip < SelectedZip && lessZipCodesTaken++ < 5) || 
(source.Zip > SelectedZip && greaterZipCodesCountTaken ++ < 5)); 
FinalCOllection.AddRange(collectionEqualToZipCode); 
FinalCOllection.AddRange(collectionlessthanOrGreaterthanZipCode);