[Development story] The second time: LINQ comes, forget foreach first

You see, LINQ has come to the full, this article is not to explore the right and wrong of LINQ, but through their own development process of a small side to show that LINQ has arrived, and better.

For technology, the biggest enemy of innovation is the transformation of the inherent thinking, not the technology itself.

1 Introduction

Today, Terry tapped my handling of a piece of code, which, as the title says, originated from my small handling of a list<t> transformation. First of all, this list<t> converts the true nature of the two sides to a common user class, for example, the user class represents the entity class of the model layer, which is defined as:

//　Release　:　code10,　2008/10/06
//　Author　:　Anytao,　http://www.anytao.com
public　class　User
{
　public　int　ID　{　get;　set;　}
　public　string　FirstName　{　get;　set;　}
　public　string　SecondName　{　get;　set;　}
　public　int　Age　{　get;　set;　}
}

The account class, then, code the business class at the business object layer, which is defined as:

//　Release　:　code10,　2008/10/06
//　Author　:　Anytao,　http://www.anytao.com
public　class　Account
{
　public　int　ID　{　get;　set;　}
　public　string　Name　{　get;　set;　}
　public　int　Age　{　get;　set;　}
}

One important thing, then, is how to make a transition between the two, especially, a transformation like list<user> to list<account>, which often happens in the actual operation of the business process. The difference between the two is a design topic, not the object of this article.

2 Original Implementation---think of foreach.

Well, the typical list<t> conversion, the thought of our inherent thinking is the loop, so I don't even think about the following process:

//　Release　:　code10,　2008/10/06
//　Author　:　Anytao,　http://www.anytao.com
public　List<Account>　GetAccounts(List<User>　users)
{
　List<Account>　accounts　=　new　List<Account> ();

　foreach　(User　item　in　users)
　{
　　Account　account　=　new　Account();
　　account.ID　=　item.ID;
　　account.Name　=　item.FirstName　+　item.SecondName;
　　account.Age　=　item.Age;
　　accounts.Add(account);
　}

　return　accounts;
}

There is nothing wrong with inherent thinking, and procedures and processes are as memorable as ever. But forgetting is just as important as moving forward, so I forget to do it the easiest way to handle the operation more gracefully.