用于绘制图形和滚动的c#面板

Question

我希望能够使用面板或类似工具将图形绘制到Winform上.如果图形变得比控件大,我似乎无法看到有关添加滚动条的任何内容？

是否可以使用面板执行此操作,或者是否存在允许它的类似控件？

谢谢.

Answer 1

将AutoScroll属性设置为true,将AutoScrollMinSize属性设置为图像的大小.现在,当图像太大时,滚动条会自动出现.

您将希望从Panel继承自己的类,以便可以在构造函数中将DoubleBuffered属性设置为true.否则闪烁会很明显.一些示例代码:

using System;
using System.Drawing;
using System.Windows.Forms;

class ImageBox : Panel {
    public ImageBox() {
        this.AutoScroll = true;
        this.DoubleBuffered = true;
    }
    private Image mImage;
    public Image Image {
        get { return mImage; }
        set {
            mImage = value;
            if (value == null) this.AutoScrollMinSize = new Size(0, 0);
            else {
                var size = value.Size;
                using (var gr = this.CreateGraphics()) {
                    size.Width = (int)(size.Width * gr.DpiX / value.HorizontalResolution);
                    size.Height = (int)(size.Height * gr.DpiY / value.VerticalResolution);
                }
                this.AutoScrollMinSize = size;
            }
            this.Invalidate();
        }
    }
    protected override void OnPaint(PaintEventArgs e) {
        e.Graphics.TranslateTransform(this.AutoScrollPosition.X, this.AutoScrollPosition.Y);
        if (mImage != null) e.Graphics.DrawImage(mImage, 0, 0);
        base.OnPaint(e);
    }
}