面板中的移动图片框

Question

我有一个 C#、WindowsForms 项目，我创建了一个 panel，其中包含一个 pictureBox，它比他的父级大得多。

我将 panel.AutoScroll 设置为 true，我想要做的是将这个 pictureBox 拖到 panel 中，而不是捕获一个卷轴并移动它。

即，当我抓取图像并将光标向左和向下移动时，我希望获得与使用面板滚动条相同的行为。

怎么办呢？

Answer 1

好的，我明白了。 ;-) 如果其他人也有同样的问题，这里是解决方案：

    protected Point clickPosition;
    protected Point scrollPosition; 

    private void pictureBox_MouseDown(object sender, MouseEventArgs e)
    {
        this.clickPosition.X = e.X;
        this.clickPosition.Y = e.Y;
    }

    private void pictureBox_MouseMove(object sender, MouseEventArgs e)
    {
        if (e.Button == MouseButtons.Left)
        {
            scrollPosition.X = scrollPosition.X + clickPosition.X - e.X;
            scrollPosition.Y = scrollPosition.Y + clickPosition.Y - e.Y;
            this.panel.AutoScrollPosition = scrollPosition;
        }
    }  

Answer 2

hsz 解决方案的较小变体:)

    protected Point clickPosition;
    protected Point scrollPosition;

    private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
    {
        this.clickPosition = e.Location;            
    }

    private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
    {
        if (e.Button == MouseButtons.Left)
        {
            this.SuspendLayout();
            this.scrollPosition += (Size)clickPosition - (Size)e.Location;
            this.panel1.AutoScrollPosition = scrollPosition;                    
            this.ResumeLayout(false);
        }
    }

Answer 3

hsz' 的改进解决方案，具有滚动限制，但我只允许垂直滚动

protected Point clickPosition;
protected Point scrollPosition;

private void picBoxScan_MouseDown(object sender, MouseEventArgs e)
{
    this.clickPosition.X = e.X;
    this.clickPosition.Y = e.Y;
}

private void picBoxScan_MouseMove(object sender, MouseEventArgs e)
{
    if (e.Button == MouseButtons.Left)
    {
        scrollPosition.X = panelViewFile.AutoScrollPosition.X;
        scrollPosition.Y = scrollPosition.Y + (clickPosition.Y - e.Y);
        scrollPosition.Y = Math.Min(scrollPosition.Y,panelViewFile.VerticalScroll.Maximum);
        scrollPosition.Y = Math.Max(scrollPosition.Y,panelViewFile.VerticalScroll.Minimum);
        panelViewFile.AutoScrollPosition = scrollPosition;
    }
}