将按钮控件添加到SplitContainer Splitter

Question

有没有办法在可调整分割器上显示控件（如按钮），该分割器显示在.NET SplitContainer中的两个面板之间？

示例：

我不认为SplitContainer本身支持这一点，但是覆盖控件以获得在许多应用程序中看起来无处不在的功能对我来说似乎有点太多了 - 我觉得我在想这个或者遗漏了一些明显的东西。

Answer 1

这是一个使用TableLayoutPanel来模拟SplitContainer的示例。

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

class Form1 : Form
{
    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new Form1());
    }

    TableLayoutPanel rootPanel;
    float originalWidth;
    int splitPointX;

    public Form1()
    {
        Controls.Add(rootPanel = new TableLayoutPanel
        {
            ColumnCount = 3,
            ColumnStyles =
            {
                // Notice the use of Absolute here as this will control the 'splitting'
                new ColumnStyle(SizeType.Absolute, 120F),
                // Size of button panel
                new ColumnStyle(SizeType.AutoSize),
                // Remaining size
                new ColumnStyle(SizeType.Percent, 100F),
            },
            Dock = DockStyle.Fill,
            RowCount = 1,
            RowStyles = { new RowStyle(SizeType.Percent, 100F) },
        });

        Panel buttonPanel;
        rootPanel.Controls.Add(buttonPanel = new Panel
        {
            Anchor = AnchorStyles.Top | AnchorStyles.Bottom,
            BackColor = SystemColors.ControlDark,
            Margin = new Padding(0),
            MinimumSize = new Size(80, 0),
            Size = new Size(80, 0),
            Controls =
            {
                // UseVisualStyleBackColor = true only because we altered the container's BackColor
                new Button { Text = ">>", Location = new Point(19, 112), Size = new Size(40, 23), UseVisualStyleBackColor = true },
                new Button { Text = ">", Location = new Point(19, 83), Size = new Size(40, 23), UseVisualStyleBackColor = true },
                new Button { Text = "<", Location = new Point(19, 54), Size = new Size(40, 23), UseVisualStyleBackColor = true },
                new Button { Text = "<<", Location = new Point(19, 25), Size = new Size(40, 23), UseVisualStyleBackColor = true },
            },
        }, 1, 0);

        buttonPanel.MouseDown += (s, e) =>
            {
                if (e.Button == MouseButtons.Left)
                {
                    // Capture mouse so that all mouse move messages go to this control
                    (s as Control).Capture = true;

                    // Record original column width
                    originalWidth = rootPanel.ColumnStyles[0].Width;

                    // Record first clicked point
                    // Convert to screen coordinates because this window will be a moving target
                    Point windowPoint = (s as Control).PointToScreen(e.Location);
                    splitPointX = windowPoint.X;
                }
            };
        buttonPanel.MouseMove += (s, e) =>
            {
                if ((s as Control).Capture)
                {
                    Point windowPoint = (s as Control).PointToScreen(e.Location);

                    // Calculate distance of mouse from splitPoint
                    int offset = windowPoint.X - splitPointX;

                    // Apply to originalWidth
                    float newWidth = originalWidth + offset;

                    // Clamp it.
                    // The control in the left pane's MinimumSize.Width would be more appropriate than zero
                    newWidth = Math.Max(0, newWidth);

                    // Update column width
                    if (Math.Abs(newWidth - rootPanel.ColumnStyles[0].Width) >= 1)
                        rootPanel.ColumnStyles[0].Width = newWidth;
                }
            };
        buttonPanel.MouseUp += (s, e) =>
            {
                if (e.Button == MouseButtons.Left)
                {
                    // Release mouse capture
                    if ((s as Control).Capture)
                        (s as Control).Capture = false;
                }
            };
    }
}