What is the difference between const and static read-only?

C# Interview Questions and Answers

(Continued from previous question...)

74. What is the difference between const and static read-only?

The difference is that static read-only can be modified by the containing class, but const can never be modified and must be initialized to a compile time constant. To expand on the static read-only case a bit, the containing class can only modify it: -- in the variable declaration (through a variable initializer).
-- in the static constructor (instance constructors if it's not static).

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