使用列表的IF语句<Bitmap>

Question

So I have looked through a few previous solutions but thus far have not seen any to fix my issue. I am trying to change a player's avatar when they click the picturebox. I have a list of images like so :

List<Bitmap> avatars = new List<Bitmap>();

private void GameForm_Load(object sender, EventArgs e)
{
  avatars.Add(Properties.Resources.Head1);
  avatars.Add(Properties.Resources.Head2);
  avatars.Add(Properties.Resources.Head3);
  avatars.Add(Properties.Resources.Head4);
}

And this is where I am trying to change it at :

private void pictureBoxAvatar1_Click(object sender, EventArgs e)
{

  if(pictureBoxAvatar1.Image == avatars.ElementAt(0))
  {
    pictureBoxAvatar1.Image = avatars.ElementAt(1);
  }
  //I have four total possibilities, but just have this one statement until I figure it out

}

My issue is that I cannot find a condition to evaluate to switch the image.

Answer 1

There are problems with your approach which if changed might make things easier. First is that for each avatar you store a copy of the Image when you only need to store one copy per image. While this is fine in small programs it will not scale well. While the compiler might be smart enough to store each of the images only once, you run a big chance of creating a lot of redundant data and we shouldn't trust the compiler to handle this for us. Of course this might change our render approach a little but it should improve caching and allow the program to run a little faster.

The better solution would be to store the Images in one central location and for the avatars store a single pointer indicating which Images to use.

I would change pictureBoxAvatar1.Image to something along the lines of pictureBoxAvatar1.ImagePointer and then your function should become something like

private void pictureBoxAvatar1_Click(object sender, EventArgs e)
{
   pictureBoxAvatar1.ImagePointer = (pictureBoxAvatar1.ImagePointer + 1) % avatars.size(); 
}

Answer 2

Something like

int avIndex = avatars.IndexOf(picturebox1.image);
avIndex++;
if (avIndex >= avatars.Count)
{ 
  avIndex = 0;
}
picturebox1.image = avatars[avIndex];

or equivalent depending on what avatars is.