.NET How can i set field value on value type using reflection
.NET I want to clone a value type's fields. How can i set a field value on a value type using reflection (or something else dynamically)?
This works for reference 开发者_StackOverflow社区types but not for value types. I understand why but I don't know an alternative.
shared function clone(of t)(original as t) as t
dim cloned as t
'if class then execute parameterless constructor
if getType(t).isClass then cloned = reflector.construct(of t)()
dim public_fields = original.getType.getFields()
for each field in public_fields
dim original_value = field.getValue(original)
'this won't work for value type, but it does work for reference type ???
field.setValue(cloned, original_value)
next
return cloned
end function
If it is a value type then you are done quick, just return "original":
'if class then execute parameterless constructor
If GetType(t).IsClass Then
Dim types(-1) As Type
cloned = DirectCast(GetType(t).GetConstructor(types).Invoke(Nothing), t)
Else
Return original
End If
You'll have more trouble making this truly universal, a type doesn't have to have a parameter-less constructor. Try a String for example.
Since value types are passed by value, SetValue
is being called on a copy of the object.
If T
is a value type, you can simply write Return original
and it will return a copy.
For example:
If GetType(T).IsValueType Then Return original
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