属性和字段不是一对一的。属性是关于类的接口(无论是谈论它的公共接口还是内部接口)，而字段是关于类的实现。属性不应该被视为仅仅公开字段的一种方式，它们应该被视为公开类的意图和目的的一种方式。

Just like you use properties to present a contract to your consumers on what constitutes your class, you can also present a contract to yourself for very similar reasons. So yes, I do use private properties when it makes sense. Sometimes a private property can hide away implementation details like lazy loading, the fact that a property is really a conglomeration of several fields and aspects, or that a property needs to be virtually instantiated with each call (think DateTime.Now). There are definitely times when it makes sense to enforce this even on yourself in the backend of the class.

惰性初始化是它们可以很整洁的一个地方，例如。

private Lazy<MyType> mytype = new Lazy<MyType>(/* expensive factory function */);

private MyType MyType { get { return this.mytype.Value; } }

// In C#6, you replace the last line with: private MyType MyType => myType.Value;

然后你可以写:this。MyType而不是this.mytype.Value，并封装了它在单个位置被惰性实例化的事实。

一个遗憾的是c#不支持将支持字段的作用域定义为属性(即在属性定义中声明它)来完全隐藏它，并确保它只能通过属性访问。

属性和字段不是一对一的。属性是关于类的接口(无论是谈论它的公共接口还是内部接口)，而字段是关于类的实现。属性不应该被视为仅仅公开字段的一种方式，它们应该被视为公开类的意图和目的的一种方式。

Just like you use properties to present a contract to your consumers on what constitutes your class, you can also present a contract to yourself for very similar reasons. So yes, I do use private properties when it makes sense. Sometimes a private property can hide away implementation details like lazy loading, the fact that a property is really a conglomeration of several fields and aspects, or that a property needs to be virtually instantiated with each call (think DateTime.Now). There are definitely times when it makes sense to enforce this even on yourself in the backend of the class.

显式字段的一些更奇特的用法包括:

你需要使用ref或out的值-可能因为它是一个联锁计数器 它旨在表示基本布局，例如在具有显式布局的结构上(可能映射到c++转储或不安全代码) 在历史上，该类型一直与带有自动字段处理的BinaryFormatter一起使用(更改为auto-props会更改名称，从而破坏序列化器)

我不时地使用它们。当你可以轻松地在属性中添加断点或添加日志记录语句时，它们可以使调试变得更容易。

如果您稍后需要以某种方式更改数据类型或需要使用反射，那么它也很有用。

我在序列化中使用它们，比如DataContractSerializer或protobuf-net，它们支持这种用法(XmlSerializer不支持)。如果你需要简化一个对象作为序列化的一部分，它是有用的:

public SomeComplexType SomeProp { get;set;}
[DataMember(Order=1)]
private int SomePropProxy {
    get { return SomeProp.ToInt32(); }
    set { SomeProp = SomeComplexType.FromInt32(value); }
}