什么时候不要在 C# 中使用 static 关键字？

Question

What makes it a poor practice to use static keyword when defining a method in C#? I know that with static we can reach directly to the function in the class without creating an instance of the class. But when we shouldn't use static?

Answer 1

There is a complete explanation for the use of the 'static' property here by Microsoft.

In a web framework's experience (.NET Core for this) for instance, we use static declaration for primitive values that WILL NOT require any change.

Answer 2

A method that does not access any instance data should actually be marked as static : https://docs.microsoft.com/en-us/visualstudio/code-quality/ca1822-mark-members-as-static?view=vs-2017 It might still be declared as a private method depending on the usage.

If the method does access any instance data it cannot be static. The compiler enforces this.

Common examples of static methods are for example String.Format and Int32.Parse . It makes no sense to allocate a string or an int before calling these methods.

Answer 3

You create a static method when you don' t need the method to access any of the non-static elements on your class. For example take in account DateTime.Parse method. You can create an instance of DateTime as usual but if you need to parse a specific date, you can call DateTime.Parse to return a valid DateTime without creating a DateTime instance per se. As that method does not access any specific element of DateTime class, it is declared as static

More info:

https://www.codeproject.com/Questions/1208992/When-to-use-static-methods-Csharp

https://hackernoon.com/c-static-vs-instance-classes-and-methods-50fe8987b231