C# Tutorials:private constructor vs static classes

Static class can not have non static members. A static class can be used as a convenient container for sets of methods that just operate on input parameters and do not have to get or set any internal instance fields. For example, in the .NET Framework Class Library, the static “Console”class contains methods that perform operations writing to console and Reading from Console, without any requirement to store or retrieve data that is unique to a particular instance of the Console class. That is, you apply the members of the class by specifying the class name and the method name.

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