而不for循环

Question

我已经以下类

public class Product 
{ 
    public int Id { get; set; } 
    public string Name { get; set; } 
    public int CategoryId { get; set; } 
    public int SectionId { get; set; } 
    public string VendorName { get; set; } 
} 

public class ProductToRemove 
{ 
    public int CategoryId { get; set; } 
    public int SectionId { get; set; } 
} 

在主我有这两个类如下的列表有效去除数据。

List<Product> Products = new List<Product>() 
{ 
    new Product() { Id = 1, Name = "A", CategoryId = 11, SectionId = 6, VendorName = "ABC" }, 
    new Product() { Id = 2, Name = "B", CategoryId = 21, SectionId = 6, VendorName = "ABC" }, 
    new Product() { Id = 3, Name = "C", CategoryId = 13, SectionId = 8, VendorName = "ABC" }, 
    new Product() { Id = 4, Name = "D", CategoryId = 90, SectionId = 6, VendorName = "ABC" }, 
    new Product() { Id = 5, Name = "E", CategoryId = 25, SectionId = 9, VendorName = "ABC" }, 
}; 

    List<ProductToRemove> ProductsToRemove = new List<ProductToRemove>() 
    { 
     new ProductToRemove() {CategoryId = 11, SectionId = 6, }, 
     new ProductToRemove() {CategoryId = 90, SectionId = 6, } 
    }; 

我想从产品实例中删除任何其中CategoryId和SectionId与ProductsToRemove集合中的内容相同的任何实例。我知道如何通过产品收集循环和删除匹配的记录，但我想知道如果有一种方法使用LINQ

Answer 1

Products.RemoveAll(x => ProductsToRemove 
    .Any(r => x.CategoryId == r.CategoryId && x.SectionId == r.SectionId)); 

Answer 2

做同样可以在Any()组合使用Where()以达到所需的输出：

var deletion = Products 
    .Where(product=> ProductsToRemove 
        .Any(remove=> product.CategoryId == remove.CategoryId 
           && product.SectionId == remove.SectionId 
         ) 
     ); 

Answer 3

List<Product> Products = new List<Product>() 
{ 
    new Product() { Id = 1, Name = "A", CategoryId = 11, SectionId = 6, VendorName = "ABC" }, 
    new Product() { Id = 2, Name = "B", CategoryId = 21, SectionId = 6, VendorName = "ABC" }, 
    new Product() { Id = 3, Name = "C", CategoryId = 13, SectionId = 8, VendorName = "ABC" }, 
    new Product() { Id = 4, Name = "D", CategoryId = 90, SectionId = 6, VendorName = "ABC" }, 
    new Product() { Id = 5, Name = "E", CategoryId = 25, SectionId = 9, VendorName = "ABC" }, 
}; 

List<Product> catsRemoved = Products.Where(x => x.CategoryId != 11 && x.CategoryId != 90).ToList(); 

Answer 4

你可以使用LINQ的方法除外：https://msdn.microsoft.com/en-us/library/bb300779(v=vs.110).aspx