clarify the "return default" usage and what value it returns

Question

Hi, can someone explains to me what is this "return default" default means? Or where in VS code I can check the value of default? I try to step into the default to see the value, but it cannot be clicked. I also looked at the docs provided from Microsoft (https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/default)

It provided 3 cases when default is used, I still don't understand this is which case. Below is the code where at the last line is using default:

        try  
        {  
            var json =  
                JsonConvert.DeserializeObject<AEGDeadLetterEvent<AEGGridEvent<AEGEventData<>>>(rawJson);  
            if (json != null)  
            {  
                Logger.Debug($"Successfully parsed AEG DeadLetter grid event as json");  
                return json;  
            }  
            else  
            {  
                Logger.Debug(string.Format("JSON parsed as null"));  
                return default;  
            }  
        }  

Thanks in advance!

Answer 1

Since you have C# code, why did you use the forum tag
for Visual Basic? You should remove that tag and use
the C# tag instead: dotnet-csharp

As to default in your code, it appears to be the
default literal case as described in the docs:

"Beginning with C# 7.1, you can use the default literal to
produce the default value of a type when the compiler can
infer the expression type. The default literal expression
produces the same value as the default(T) expression where
T is the inferred type."

So the line

return default;

should return the default value for whatever the return
type of the method in question has declared/defined.

• Wayne

Answer 2

This is the second case.

It will return the default value of that type according to the return value type, the reference type returns null, the int type returns 0, the bool type returns false, etc.

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