与多个转换LINQ查询表达式320交织成扩展方法的语法 [英] Convert linq query expression with multiple froms into extension method syntax

问题描述

我有麻烦的代码转换为扩展方法的语法：

  VAR的查询=从C在_context.Customers $ B从o在c.Orders 
 $ b，其中o.DateSent == NULL 
选择新CustomerSummary 
 {
 n = c.Id，
 =用户名c.Username ，
 OutstandingOrderCount = c.Orders.Count 
}; 
  

任何想法？

解决方案

  VAR的查询= _context.Customer 
。凡（C => c.Orders.Any（O = GT; o.DateSent == NULL） ）
。选择（C =>新建CustomerSummary 
 {
 n = c.Id，
 =用户名c.Username，
 OutstandingOrderCount = c.Orders.Count （O => o.DateSent == NULL）
}; 
  

I am having trouble converting this code into extension method syntax:

var query = from c in _context.Customers
                        from o in c.Orders
                        where o.DateSent == null
                        select new CustomerSummary
                        {
                            Id = c.Id,
                            Username = c.Username,
                            OutstandingOrderCount = c.Orders.Count
                        };

Any ideas?

解决方案

var query = _context.Customer
  .Where(c => c.Orders.Any(o => o.DateSent == null))
  .Select(c => new CustomerSummary
  {
    Id = c.Id,
    Username = c.Username,
    OutstandingOrderCount = c.Orders.Count(o => o.DateSent == null)
  };

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