Does `ToList()` Create a Truly Independent List of Objects?

Does ToList() Create a New List and Independent Objects?

When dealing with reference types, it's essential to understand the behavior of ToList(). While it may create a new list, the underlying objects may still reference the ones in the original list.

Instance:

Consider a class MyObject with a property SimpleInt. A list of MyObjects (objs) is created, and an additional list is generated by invoking ToList() on objs.

Function Analysis:

The ChangeToList method accepts a parameter of type List and does the following:

1. Invokes ToList() on the parameter object, creating objectList.
2. Modifies the SimpleInt property of the first element in objectList.
3. Returns the SimpleInt property of the first element in the original list (objs).

Result:

Due to MyObject being a reference type, the objectList references the same objects as objs. Therefore, updating objectList[0].SimpleInt also modifies objs[0].SimpleInt.

Hence, in the given example, the ChangeToList method will return 5, indicating that the change propagated back to the original list. To summarize, ToList() creates a new list, but the elements it contains may still reference objects in the original list. This behavior is particularly relevant when working with reference types like classes or arrays.

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