在 .NET 中,如果一个类包含一个作为类对象的成员,该成员应该作为属性公开还是使用方法公开?
最佳答案
您应该为任何概念上表示对象状态的东西使用属性,只要它的检索不是一个足够昂贵的操作,您应该避免重复使用它。
来自 MSDN :
Class library designers often must decide between implementing a class member as a property or a method. In general, methods represent actions and properties represent data. Use the following guidelines to help you choose between these options.
Use a property when the member is a logical data member. In the following member declarations, Name is a property because it is a logical member of the class.
public string Name get { return name; } set { name = value; }
Use a method when:
- The operation is a conversion, such as Object.ToString.
- The operation is expensive enough that you want to communicate to the user that they should consider caching the result.
- Obtaining a property value using the get accessor would have an observable side effect.
- Calling the member twice in succession produces different results.
- The order of execution is important. Note that a type's properties should be able to be set and retrieved in any order.
- The member is static but returns a value that can be changed.
The member returns an array. Properties that return arrays can be very misleading. Usually it is necessary to return a copy of the internal array so that the user cannot change internal state. This, coupled with the fact that a user can easily assume it is an indexed property, leads to inefficient code. In the following code example, each call to the Methods property creates a copy of the array. As a result, 2n+1 copies of the array will be created in the following loop.
Type type = // Get a type. for (int i = 0; i < type.Methods.Length; i++) { if (type.Methods[i].Name.Equals ("text")) { // Perform some operation. } }
The following example illustrates the correct use of properties and methods.
class Connection { // The following three members should be properties // because they can be set in any order. string DNSName {get{};set{};} string UserName {get{};set{};} string Password {get{};set{};} // The following member should be a method // because the order of execution is important. // This method cannot be executed until after the // properties have been set. bool Execute (); }
关于.net - 在 .NET 中将成员对象公开为属性或方法,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/164527/