Linq按产品排序，但显示cigogire

Question

所以我有一个问题，代码是选择一个类别 ，我需要改变排序顺序按product.Name然后按category.name。

但问题是我仍然想选择一个类别，但是如何在不添加额外连接或选择的情况下先按product.name排序 。

从类别中的类别选择 category.name 的OrderBy category.Name //排序依据类别名称

后来在视图我环的foreach（category.products），并通过在category.product [I]，以查看以显示

但排序顺序是错误的，顺序总是由Category.Name 如何按Product.Name第一次，然后通过Category.Name？ 请问SelectMany有帮助吗？再次，我不想破坏我的查询中的选择 部分，只是按东西排序。

class产品 { public string Name {get;组; } public int CategoryID {get;组; } }

class Category { public string Name {get;组; } public int ID {get;组; } }

//指定第一个数据源。 静态列表类别=新列表（） { 新分类（）{名称= “饮料”，ID = 001}， 新分类（）{名称= “调味品”，ID = 002}， 新的类别（） {Name =“Vegetables”，ID = 003} 新类别（）{Name =“Grains”，ID = 004}，

//指定第二个数据源。新产品{Name =“Cola”，CategoryID = 001}， 新产品{Name =“Tea”，CategoryID = 001}， 新产品{Name =“Mustard” ，CategoryID = 002}， 新产品{Name =“pickles”，CategoryID = 002}， 新产品{Name =“Carrots”，CategoryID = 003}， 新产品{Name =“Bok Choy”，CategoryID = 003 }， 新产品{Name =“Peaches”，CategoryID = 005}， 新产品{Name =“Melons”，CategoryID = 005}， };

Answer 1

哦，我看到你的查询，它格式不正确。

您需要order by Product.Name group by Category.Name

Answer 2

//LinqPad code 

class Category 
{ 
    public string Name { get; set; } 
    public int ID { get; set; } 
    public List<Product> products { get; set;} 
} 

class Product 
{ 
    public string Name { get; set; } 
    public int ID { get; set; } 
} 


void Main() 
{ 
     // Specify the second data source. 
     List<Product> BevProducts = new List<Product>() 
     { 
      new Product{Name="ZCola"}, 
     }; 

     // Specify the third data source. 
     List<Product> CondProducts = new List<Product>() 
     { 
      new Product{Name="Sugar"}, 
     }; 
     // Specify the first data source. 
    List<Category> categories = new List<Category>() 
     { 
      new Category(){Name="Beverages", ID=001, products=BevProducts}, 
      new Category(){ Name="Condiments", ID=002, products=CondProducts}, 

     }; 



     var sortedCats = categories.OrderBy(c => c.ID).ToList(); 

     foreach (var category in sortedCats) 
     { 
      //display category 
      System.Console.Out.WriteLine(category.Name); 

     //Assuming each category contains exactly one product in the list ie 1 to 1 relationship 
// how can I sort by product.Name, so if ZCola comes before Sugar, ZCola's Category (Beverages) sorts before Condiments 
// so in this Case Beverages, Condiments is the right order, because ZCola comes after Sugar. 
      var sortedProductsPerCategory = category.products.OrderBy(p => p.Name).ToList(); 

      foreach (var product in sortedProductsPerCategory) 
      { 
        //display product 
        System.Console.Out.WriteLine(" " + product.Name); 
      } 
     } 



} 

Answer 3

class Category 
{ 
    public string Name { get; set; } 
    public int ID { get; set; } 
    public List<Product> products { get; set;} 
} 

class Product 
{ 
    public string Name { get; set; } 
    public int ID { get; set; } 
} 


void Main() 
{ 
     // Specify the second data source. 
     List<Product> BevProducts = new List<Product>() 
     { 
      new Product{Name="ZCola"}, 
     }; 

     // Specify the third data source. 
     List<Product> CondProducts = new List<Product>() 
     { 
      new Product{Name="Sugar"}, 
     }; 
     // Specify the first data source. 
    List<Category> categories = new List<Category>() 
     { 
      new Category(){Name="Beverages", ID=001, products=BevProducts}, 
      new Category(){ Name="Condiments", ID=002, products=CondProducts}, 

     }; 



     var sortedCats = categories.OrderBy(c => c.products.Min(p => p.Name)).ToList(); 

     foreach (var category in sortedCats) 
     { 
      //display category 
      System.Console.Out.WriteLine(category.Name); 


      //Assuming each category contains exactly one product in the list ie 1 to 1 relationship 
      // how can I sort by product.Name, so if ZCola comes before Sugar, ZCola's Category (Beverages) sorts before Condiments 
      // so in this Case Beverages, Condiments is the right order, because ZCola comes after Sugar. 
      var sortedProductsPerCategory = category.products.OrderBy(p => p.Name).ToList(); 

      foreach (var product in sortedProductsPerCategory) 
      { 
        //display product 
        System.Console.Out.WriteLine(" " + product.Name); 
      } 
     } 



}