在 C Sharp 中调整自定义表单的大小（具有投影效果）和鼠标拖动事件的控件？

Question

在我的应用程序中，我必须调整表单的大小及其对鼠标拖动效果的所有控制，并且表单应该具有阴影效果，问题是我的所有表单都是自定义表单（没有边框）。

提前致谢

Answer 1

我认为你必须自己实现

1. 鼠标按下开始绑定鼠标拖动+更改光标以调整
2. 鼠标拖动上的图标大小，只需简单地减小
3. 鼠标向上解除绑定鼠标拖动事件的

表单大小我建议动态事件绑定的原因，以便你可以指定哪个控件或区域应该按下鼠标

Answer 2

我不确定投影效果，但您应该能够通过在右下角放置一个按钮和一些适当的图标来调整表单的大小。当用户单击并拖动此按钮时，它会调整表单的大小。这是一些示例代码：

public partial class Form1 : Form
{
    private int bottomBorder;
    private int rightBorder;
    private Point mouseStart;
    private bool isResizing = false;

    public Form1()
    {
        InitializeComponent();
    }

    private void button1_MouseMove(object sender, MouseEventArgs e)
    {
        if (isResizing)
        {
            var newLocation = button1.Location;
            newLocation.Offset(
                e.X - mouseStart.X,
                e.Y - mouseStart.Y);
            button1.Location = newLocation;
            this.Height = button1.Bottom + bottomBorder;
            this.Width = button1.Right + rightBorder;
            button1.Refresh();
        }

    }

    private void button1_MouseDown(object sender, MouseEventArgs e)
    {
        isResizing = true;
        mouseStart = e.Location;
    }

    private void button1_MouseUp(object sender, MouseEventArgs e)
    {
        isResizing = false;
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        bottomBorder = this.Height - button1.Bottom;
        rightBorder = this.Width - button1.Right;
    }
}

Answer 3

如果没有边框（或某些控件），您打算如何调整大小？找出该部分，然后在表单中尝试此代码：

public class CustomForm : Form
{
    private const int WmNcLButtonDown = 0xA1;
    private const int HtBottomRight = 17;

    [DllImport("user32.dll")]
    private static extern int ReleaseCapture();

    [DllImport("user32.dll")]
    private static extern int SendMessage(IntPtr hwnd, int msg, int wparam, int lparam);

    // elsewhere
    void ResizeForm()
    {
        ReleaseCapture();
        SendMessage(this.Handle, WmNcLButtonDown, HtBottomRight, 0);
    }
}

此代码将调整表单的大小，就像使用了右下角一样。查找 HT_BOTTOMRIGHT 和其他 HT_ 常量以了解不同位置的大小调整。

Answer 4

我使用了 Don Kirkby 和 Matthew Ferreira 的解决方案，并结合两者创建了我自己的解决方案。我添加了一个名为“resizeHandle”的 StatusStrip，使其大小为 20x20 像素并监听其事件。

public class CustomForm : Form
{
private const int WmNcLButtonDown = 0xA1;
private const int HtBottomRight = 17;
private const int wmNcLButtonUp = 0xA2;
private bool isResizing = false;

[DllImport("user32.dll")]
private static extern int ReleaseCapture();

[DllImport("user32.dll")]
private static extern int SendMessage(IntPtr hwnd, int msg, int wparam, int lparam);

private void resizeHandle_MouseDown(object sender, MouseEventArgs e)
{
    isResizing = true;
}

private void resizeHandle_MouseMove(object sender, MouseEventArgs e)
{
    if (isResizing)
    {
        // Check if we have released the Left mouse button
        isResizing = (e.Button == MouseButtons.Left);
        ReleaseCapture();
        if (isResizing)
        {
            SendMessage(Handle, wmNcLButtonDown, HtBottomRight, 0);
        }
        else
        {
            // Left Mouse button was released, end resizing.
            SendMessage(Handle, wmNcLButtonUp, HtBottomRight, 0);
        }
    }
}