tarafdarmansour/ref-vs-out-parameter-in-csharp

Difference between Ref and Out keywords in C#

I think it is simple but important.

No.	Key	ref keyword	out keyword
1	Purpose	ref keyword is used when a called method has to update the passed parameter.	out keyword is used when a called method has to update multiple parameter passed.
2	Direction	ref keyword is used to pass data in bi-directional way.	out keyword is used to get data in uni-directional way.
3	Initialization (in parent method)	Before passing a variable as ref, it is required to be initialized otherwise compiler will throw error.	No need to initialize variable if out keyword is used.
4	Initialization (in called method)	In called method, it is not required to initialize the parameter passed as ref.	In called method, it is required to initialize the parameter passed as out.

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