C# - Resize Image after upload

Question

I'm trying to resize the image after upload but it doesn't work

What's wrong?

   private void button1_Click(object sender, EventArgs e)
    {
    OpenFileDialog open = new OpenFileDialog(); 

     open.Filter = "Image Files(*.jpg; *.jpeg; *.gif; *.bmp)|*.jpg; *.jpeg; *.gif; *.bmp"; 
       if (open.ShowDialog() == DialogResult.OK)
    {
        var imagem = new Bitmap(open.FileName);
        var resizedImage = new Bitmap(imagem, pictureBox1.Size);
       pictureBox1.Image = resizedImage;
        } 

 }

PictureBox already has the ability to resize an image like this, Set the BackgroundImageLayout property to Stretch. It will make the image the same size as the PictureBox — musefan
– musefan, Commented Jan 11, 2013 at 16:54
why down vote? I have said what happens...The image appears not full in picture box...appears cropped — Ladessa
– Ladessa, Commented Jan 11, 2013 at 16:59
Re-read your question, your comment is the first time you told us. — Scott Chamberlain
– Scott Chamberlain, Commented Jan 11, 2013 at 17:01
I have said that I'm trying resize the image but doesnt work..if I'm trying resize an image and it doesn't work...theeem the image was not resized...It's obvious — Ladessa
– Ladessa, Commented Jan 11, 2013 at 17:03

musefan · Accepted Answer · 2013-01-11 17:14:26Z

3

PictureBox already has the ability to resize an image.

If you are assigning the image using the Image property then you can set the SizeMode property to StretchImage. Which means you code would look like this:

var imagem = new Bitmap(open.FileName);
pictureBox1.Image = imagem;

If you want to assign the image using the BackgroundImage property then you can set the BackgroundImageLayout property to Stretch. Which means you code would look like this:

var imagem = new Bitmap(open.FileName);
pictureBox1.BackgroundImage = imagem;

From personal experience I have found the PictureBox control to be a pain. If you are needing to change or remove the image at any point I always found I needed to explicitly dispose of the image or it gave me memory leaks, and in some cases just plain errors. It is worth noting that when you need to do custom drawing or rendering in WinForms then the Panel control is a much better option. You can draw images onto a Panel too, but depending on your needs, you may be find just using the PictureBox

edited Jan 11, 2013 at 17:14

answered Jan 11, 2013 at 17:06

musefan

48.5k21 gold badges144 silver badges193 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Scott Chamberlain Over a year ago

I think you have the wrong property, he needs SizeMode

Scott Chamberlain · Accepted Answer · 2013-01-11 17:04:56Z

1

You need to set the SizeMode of your picture box

from the MSDN

By default, in Normal mode, the Image is positioned in the upper-left corner of the PictureBox, and any part of the image that is too big for the PictureBox is clipped. Using the StretchImage value causes the image to stretch or shrink to fit the PictureBox. Using the Zoom value causes the image to be stretched or shrunk to fit the PictureBox; however, the aspect ratio in the original is maintained.

So change the setting on PictureBox1 from Normal to StretchImage or Zoom depending on which affect you want. It will make it act how you want and you can remove your resize code.

answered Jan 11, 2013 at 17:04

Scott Chamberlain

128k37 gold badges299 silver badges448 bronze badges

Comments

Tony Hopkinson · Accepted Answer · 2013-01-11 17:16:33Z

1

Well you don't need this code, just set the SizeMode Property to StretchImage. However the extremely irritating reason your code doesn't work, is changing from one image to another does not in and of itself trigger the picture box to redraw.

The two usual solutions are to either

Call pictureBox1.Invalidate() after you assign the image, or do pictureBox1.Image = null, before you assign it.

You might have to do one of these even with SizeMode set, if the image is the same size as the PictureBox, can't remember.

answered Jan 11, 2013 at 17:16

Tony Hopkinson

20.4k3 gold badges35 silver badges40 bronze badges

Collectives™ on Stack Overflow

C# - Resize Image after upload

3 Answers 3

1 Comment

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related