Question

I am creating a simple form based message display system, each message is a jpeg image, what I want to achieve is when the program loads (just after a user has logged on) one of the jpg’s is randomly selected and shown, if the user clicks the Next button another jpg is shown until all have been displayed. I think I need to read each image into an array and then randomly select one from the array and then when a user clicks Next move on to the next item in the array. One caveat is that I don’t want the program to lock open the jpg files as others need to be able to delete them.

My current code is below, I would appreciate any help and advice you can offer.

private void Form1_Load(object sender, EventArgs e)
 {
      var rand = new Random();
      var files = Directory.GetFiles(@"\\server\screens\", "*.jpg");
      pictureBox1.Image = System.Drawing.Bitmap.FromFile(files[rand.Next(files.Length)]);  
 }

private void buttonNextImage_Click(object sender, EventArgs e)
 {
      var rand = new Random();
      var files = Directory.GetFiles(@"\\server\screens\", "*.jpg");
      pictureBox1.Image = System.Drawing.Bitmap.FromFile(files[rand.Next(files.Length)]);
 }

Many thanks
Steven

Answer 1

Don’t use Bitmap.FromFile, use Bitmap.FromStream:

using(var fs = new FileStream(files[rand.Next(files.Length),
                              FileMode.Open, FileAccess.Read))
{
    pictureBox1.Image = System.Drawing.Bitmap.FromStream(fs);
}

I don’t know how to create an array of images

var files = Directory.GetFiles("\\\\server\\screens\\", "*.jpg");
var images = new Image[files.Length];
for(int i = 0; i < files.Length; ++i)
{
    using(var fs = new FileStream(files[i], FileMode.Open, FileAccess.Read))
    {
        images[i] = System.Drawing.Image.FromStream(fs);
    }
}