How to pass x.ToString () to a method that expects an object type, not just x to prevent boxing?

Question

I have a method called OutputToScreen(object o), and it is defined as:

public void OutputToScreen(object o)
{
    Console.WriteLine(o.ToString());
}

In my main calling method, if I do something like:

int x = 42;
OutputToScreen(x); // x will be boxed into an object

But if I do this,

OutputToScreen(x.ToString()); // x is not boxed

I'm still not sure why x does not fit in the box in the second approach, I just saw it on the free video from quickcert. Can anyone give a good explanation?

Here is another comment based question:

If I pass x.ToString (), which looks like:

string temp = x.ToString (); and then going through in temp, boxing still doesn't occur when I insert x into the string type

Answer 1

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int? x = null;
Console.WriteLine(x.ToString());
Console.WriteLine(x.GetType());

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:

struct S { /* does not override ToString */ }

S s = new S();
string str = s.ToString();

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http://blogs.msdn.com/b/ericlippert/archive/2011/03/14/to-box-or-not-to-box-that-is-the-question.aspx

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Answer 2

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http://weblogs.asp.net/ngur/archive/2003/12/16/43856.aspx

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public override string ToString()
{
   return Number.FormatInt32(this, null, NumberFormatInfo.CurrentInfo);
}

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int x = 42;
object boxed = x;
OutputToScreen(boxed);

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int x = 42;
string temp = x.ToString();
OutputToScreen(temp);

Answer 3

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Answer 4

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