如何将2个 LIST 通过LINQ 合并计算出想要的结果

[u011096096]

查询 用户当月利润 有进货和销售 利润为销售减去进货

    public class User
    {

       // 姓名
        public string Name { get; set; }
      // 金额
        public int Amount { get; set; }  
    }

           //所有销售汇总
            List<User> Sales = new List<User>() { 
                new User(){ Name="张三",Amount=88}, //有进货又有销售
                new User(){ Name="李四",Amount=99}      //只有销售   
                };

            // 所有进货汇总
            List<User> Purchase = new List<User>() { 
            
                new User(){ Name="张三",Amount=30},//有进货又有销售
                new User(){ Name="王五",Amount=20}  // 只有进货 
            
            };

//希望能最终通过LINQ 计算能得到 下面的匿名类输出JSON

 {Name:"张三",SaleAmount=88, PurchaseAmount=30,Profit=58},
 {Name:"李四",SaleAmount=99, PurchaseAmount=0,Profit=99},
{Name:"李四",SaleAmount=0, PurchaseAmount=20,Profit=-20}

[q107770540]

void Main()
{ 
		   //所有销售汇总
			List<User> Sales = new List<User>() { 
				new User(){ Name="张三",Amount=88}, //有进货又有销售
				new User(){ Name="李四",Amount=99}      //只有销售   
				};
 
			// 所有进货汇总
			List<User> Purchase = new List<User>() { 
			 
				new User(){ Name="张三",Amount=30},//有进货又有销售
				new User(){ Name="王五",Amount=20}  // 只有进货 
			 
			};
			 
		    var result = from p in (Sales.Select(x=>x.Name)).Union(Purchase.Select(x=>x.Name))
			             join s in Sales on p equals s.Name into ps
						 from s in ps.DefaultIfEmpty()
						 join pc in Purchase on p equals pc.Name into pcp
						 from pc in pcp.DefaultIfEmpty()
						 let salesAmount = s == null ? 0 : s.Amount
						 let purchaseAmount = pc == null? 0 : pc.Amount
						 select new 
					   	 {
						   Name = p,
						   SaleAmount  = salesAmount,
						   PurchaseAmount = purchaseAmount,
						   Profit = salesAmount - purchaseAmount
						 };
			 
			result.Dump();
}


public class User
	{
 
	   // 姓名
		public string Name { get; set; }
	  // 金额
		public int Amount { get; set; }  
	}

[q107770540]

By the way: I like the way you ask the question: provide the class definition and expected result with dummy data