Question

I have read a lot about the danger of using structures as a data type, I wonder if there is any problem with this one,

List<Summarized> SummarizedList = new List<Summarized>();
    Summarized SumInfo;
    struct Summarized
    {
        public string sBrand;
        public string sModel;
        public string sCustomer;
        public int sline;
        public string sLeader;            
        public int sDesire;
        public int sReal;               
    } 

As you can see I use a generic list of items type SumInfo which is the struct data type. whenever I need to update an item of the list I just do the following:

SumInfo = (Summarized)SummarizedList[CurrentPos];
            SumInfo.sDesire = DesireProd;
            SumInfo.sReal = RealProduced;                
            SummarizedList[CurrentPos] = SumInfo;

where CurrentPos is the position of the item I want to update.

Everything works fine so far, so could be any problem with that in the future? Is this struct one of the mutable ones?

Thanks.

Answer 1

Everything works fine so far, so could be any problem with that in the future? Is this struct one of the mutable ones?

Yes, it’s a mutable struct. Yes, it will work.

However, I would argue that this struct should be a class. For details as to why, refer to Choosing Between Classes and Structures. In this case, you’re violating 3 of the cases which should always be true for structs:

• It logically represents a single value, similar to primitive types (integer, double, and so on).
• It has an instance size smaller than 16 bytes.
• It is immutable.

This would strongly suggest a class is more appropriate for your type. It would also simplify your code.

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BTW – Side note, the cast is not required in your code above. You should be able to just write:

SumInfo = SummarizedList[CurrentPos];