LINQ中的不同元素 [英] Distinct elements in LINQ

问题描述

我有我的地方展示的产品列表为客户的情况。这样，有两种产品。所以，如果客户是registerd两款产品，那么这两个产品得到展示。所以，我需要显示不同行。我这样做：

I have a situation where i display a list of products for a customer. So, there are two kinds of products. So, if customer is registerd to two products, then both the products get displayed. So, I need to display distinct rows. I did this:

   var queryProducts = DbContext.CustomerProducts.Where(p => p.Customers_Id ==  
                                            customerID).ToList().Select(r => new
                           {
                               r.Id,
                               r.Products_Id,
                               ProductName = r.Product.Name,
                               ShortName = r.Product.ShortName,
                               Description = r.Product.Description,
                               IsActive = r.Product.IsActive

                           }).Distinct();

在此，是的customerID我从DropDownList中获得的价值。然而，它仍显示两次相同的行。那么，能不能请你让我知道我可以只显示不同的记录。

In this, customerID is the value that i get from dropdownlist. However, it still displays the same row twice. So, can you please let me know how i can display only distinct records.

推荐答案

最有可能的原因可能是DISTINCT时调用默认无参数比较所有平等的公共属性。我怀疑你的ID将是唯一的。因此，分明是不为你工作。

The most likely reasons could be that Distinct when called with no parameter by default compares all the public properties for equality. I suspect your Id is going to be unique. Hence the Distinct is not working for you.

您可以尝试像

myCustomerList.GroupBy（产品= GT; product.Products_Id）。选择（GRP => grp.First（））;

我发现这是答案

1. 的如何通过LAMBDA或LINQ从列表中得到明显的实例


2. 的鲜明的（）与拉姆达？

1. How to get distinct instance from a list by Lambda or LINQ
2. Distinct() with lambda?

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