Nested Struct Bug??

[Rene]

Please help me, add a button to a new for and copy and paste the simple code
below. According to me, the last message box in the Click event of the
button should popup a "123" but instead it pops up a "0". Why?? Is this a
bug?? Thank you.

---------------- CODE TO COPY ----------------

public struct struct1
{
public int a;
public struct2 b;
}

public struct struct2
{
public int x;
}

private void button1_Click(object sender, System.EventArgs e)
{
struct1[] arrayWithStructs = new struct1[1];
struct2 s2 = arrayWithStructs[0].b;
s2.x = 123;

MessageBox.Show(s2.x.ToString()); // Good.
MessageBox.Show(arrayWithStructs[0].b.x.ToString()); // Bad
}

[Jon Skeet [C# MVP]]

Rene <no****@nospam.nospam> wrote:

Please help me, add a button to a new for and copy and paste the simple code
below. According to me, the last message box in the Click event of the
button should popup a "123" but instead it pops up a "0". Why?? Is this a
bug?? Thank you.

It's not a bug - it's because structs are value types. When you do

struct s2 = ...;

you're creating a new copy of the value which is then completely
separate from the array.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

[Rene]

Got it, thank you.
"Jon Skeet [C# MVP]" <sk***@pobox.com> wrote in message
news:MP************************@msnews.microsoft.c om...

Rene <no****@nospam.nospam> wrote:

Please help me, add a button to a new for and copy and paste the simple code below. According to me, the last message box in the Click event of the
button should popup a "123" but instead it pops up a "0". Why?? Is this a bug?? Thank you.

It's not a bug - it's because structs are value types. When you do

struct s2 = ...;

you're creating a new copy of the value which is then completely
separate from the array.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too