.net调整大小控制不起作用？

Question

I have a couple of pictureboxes that need to be resized by aspect ratio when the window size changes. I assumed I can anchor the width, but set the height manually (ie anchor the left, right, and top edges; but not the bottom.) However, my control won't resize if I try changing the Size property. Why wouldn't that work? How can I resize my control?

    private void Form1_Resize(object sender, System.EventArgs e)
    {
        int oldWidth = 1280;
        int oldHeight = 1024;
        int newWidth = webcamPictureBox.Size.Width; // this is auto-resized w/ window; becomes 591
        int newHeight = (oldHeight * newWidth) / oldWidth; // this is calculated manually; becomes 472

        // Control won't resize if I change the Size property
        // Size property stays the same
        this.webcamPictureBox.Size = new Size(newWidth, newHeight);
        this.thumbnailPictureBox.Size = new Size(newWidth, newHeight);
    }

Answer 1

You could be running into one of a few problems, I suppose:

• What's the SizeMode of the PictureBox? Is it AutoSize , StretchImage , or something like that? It should probably be Normal for what you want to do.

• Are you sure you have your anchoring set up correctly?

• Did you debug and check the final size of the picture boxes you're trying to resize? You should verify that it's what you expect and that the form has been repainted.

These are just some ideas; your code along is not enough to provide a great response.

Answer 2

It's difficult to answer this question definitively with the information you've posted.

Windows forms controls problems are difficult to debug by nature because of all the controls that might be affecting what you're doing. First off, you'll want to try debugging this on your own on a form with as few controls as possible. Are there any circumstances under which the resizing behaves properly?

That said, is the Dock property set on these controls? They definitely won't resize if they're set to DockStyle.Fill.

Answer 3

Thanks for the ideas -- they pointed me on the right track! Everything was set up as they should be, except the TableLayoutPanel they were in was constraining their sizes. I determined this by noticing the pictureboxes' size values were simply uneditable, both in runtime and in the designer.

So I set TableLayoutPanel's AutoSize to true, and it works great!