C# 鼠标拉伸、移动控件 改变鼠标形状
作者：互联网
这是在昨天的移动控件的基础上增加了拉伸功能
代码看起来长了很多，主要是因为拉伸有8种情况
拉伸时要判断鼠标是否处于边缘，根据位置改变鼠标形状（感觉完全可以由系统直接支持啊）
用法仍然是对控件调用EnableDrag即可
关于Tag，控件都有个Tag，用来放一些用户数据，使用时需要做类型转换，我用Tag存储了控件的位置和大小，方便另外的目的（如何修改代码以便运行，代码中有说明）
class DragControl
{
private enum ResizeType { Left, Right, Top, Bottom, LeftTop, RightTop, LeftBottom, RightBottom };//拉伸的8种情况
static private int m_border = 5;//边缘宽度
static private ResizeType m_ResizeType;//拉伸操作的边框
static public bool m_OnResize = false;//处于拉伸模式
static public bool m_OnDrag = false;//处于移动模式
static private Point m_LastPoint = new Point();
//入口点，对控件调用这个
static public void EnableDrag(Control control)
{
//添加事件处理程序
control.MouseDown += new MouseEventHandler(MouseDown);
control.MouseMove += new MouseEventHandler(MouseMove);
control.MouseUp += new MouseEventHandler(MouseUp);
}
//判断鼠标是否处于边缘，获得边缘类型（四条边四个角）以及对应的光标
static private bool isBorder(Control control, Point newpoint,ref ResizeType type,ref Cursor cursor)
{
bool ret = false;
Point controlpoint = control.PointToClient(Cursor.Position);
if (controlpoint.X < m_border && controlpoint.Y < m_border)
{
type = ResizeType.LeftTop;
cursor = Cursors.SizeNWSE;
ret = true;
}
else if (controlpoint.X > control.Size.Width - m_border && controlpoint.Y < m_border)
{
type = ResizeType.RightTop;
cursor = Cursors.SizeNESW;
ret = true;
}
else if (controlpoint.X < m_border && controlpoint.Y > control.Size.Height - m_border)
{
type = ResizeType.LeftBottom;
cursor = Cursors.SizeNESW;
ret = true;
}
else if (controlpoint.X > control.Size.Width - m_border && controlpoint.Y > control.Size.Height - m_border)
{
type = ResizeType.RightBottom;
cursor = Cursors.SizeNWSE;
ret = true;
}
else if (controlpoint.X < m_border)
{
type = ResizeType.Left;
cursor = Cursors.SizeWE;
ret = true;
}
else if (controlpoint.X > control.Size.Width - m_border)
{
type = ResizeType.Right;
cursor = Cursors.SizeWE;
ret = true;
}
else if (controlpoint.Y > control.Size.Height - m_border)
{
type = ResizeType.Bottom;
cursor = Cursors.SizeNS;
ret = true;
}
else if (controlpoint.Y < m_border)
{
type = ResizeType.Top;
cursor = Cursors.SizeNS;
ret = true;
}
return ret;
}
static private void MouseDown(object sender, MouseEventArgs e)
{
m_OnResize = false;
m_OnDrag = false;
Control control = (Control)sender;
Point newpoint = control.Parent.PointToClient(Cursor.Position);
Cursor cursor = new Cursor(Cursor.Current.Handle);//Cursor的构造函数是不需要，但是下面调用的时候要求初始化过，或许这个参数应该用out
m_OnResize = isBorder(control, newpoint, ref m_ResizeType, ref cursor);
if (m_OnResize)
{
control.Cursor = cursor;
}
else
{//不是边缘就是移动模式
control.Cursor = Cursors.SizeAll;
m_OnDrag = true;
}
m_LastPoint = newpoint;
}
static private void MouseMove(object sender, MouseEventArgs e)
{
Control control = (Control)sender;
Point newpoint = control.Parent.PointToClient(Cursor.Position);//当前鼠标位置
if (!m_OnDrag && !m_OnResize)
{//还没按下鼠标，只显示光标
Cursor cursor = new Cursor(Cursor.Current.Handle);
if (isBorder(control, newpoint, ref m_ResizeType, ref cursor))
{
control.Cursor = cursor;
}
else
{
control.Cursor = Cursors.Default;
}
return;
}
Point moved = new Point(newpoint.X - m_LastPoint.X, newpoint.Y - m_LastPoint.Y);//鼠标位置变化量
//tvi里面放了几个变量，替换了即可
//tvi.m_AutoLocation bool 表明这个对象位置大小是否自动计算（是否经过了定制），就一句代码用到，删掉
//tvi.m_location Point 对象的位置，用临时变量替换即可，初值=control.Location
//tvi.m_size Size 对象的大小，用临时变量替换即可，初值=control.Size
//tvi.m_view 就是对象本身，用control替换即可
TableRelation.TableViewTag tvi = (TableRelation.TableViewTag)control.Tag;
tvi.m_AutoLocation = false;
if (m_OnDrag)
{
tvi.m_location.X += moved.X;
tvi.m_location.Y += moved.Y;
}
if (m_OnResize)
{
switch (m_ResizeType)
{
case ResizeType.Left:
tvi.m_size = new Size(control.Size.Width - moved.X, control.Size.Height);
tvi.m_location = new Point(control.Location.X + moved.X, control.Location.Y);
break;
case ResizeType.Right:
tvi.m_size = new Size(control.Size.Width + moved.X, control.Size.Height);
break;
case ResizeType.Top:
tvi.m_size = new Size(control.Size.Width, control.Size.Height - moved.Y);
tvi.m_location = new Point(control.Location.X, control.Location.Y + moved.Y);
break;
case ResizeType.Bottom:
tvi.m_size = new Size(control.Size.Width, control.Size.Height + moved.Y);
break;
case ResizeType.LeftTop:
tvi.m_size = new Size(control.Size.Width - moved.X, control.Size.Height - moved.Y);
tvi.m_location = new Point(control.Location.X + moved.X, control.Location.Y + moved.Y);
break;
case ResizeType.LeftBottom:
tvi.m_size = new Size(control.Size.Width - moved.X, control.Size.Height + moved.Y);
tvi.m_location = new Point(control.Location.X + moved.X, control.Location.Y);
break;
case ResizeType.RightTop:
tvi.m_size = new Size(control.Size.Width + moved.X, control.Size.Height - moved.Y);
tvi.m_location = new Point(control.Location.X, control.Location.Y + moved.Y);
break;
case ResizeType.RightBottom:
tvi.m_size = new Size(control.Size.Width + moved.X, control.Size.Height + moved.Y);
break;
default:
MessageBox.Show(m_ResizeType.ToString());
break;
}
}
tvi.m_view.Location = tvi.m_location;
tvi.m_view.Size = tvi.m_size;
m_LastPoint = newpoint;
}
static private void MouseUp(object sender, MouseEventArgs e)
{
Control control = (Control)sender;
control.Cursor = Cursors.Default;
m_OnResize = false;
m_OnDrag = false;
}
}
标签：control,控件,鼠标,C#,ResizeType,moved,tvi,new,Size 来源： https://www.cnblogs.com/shadowpigg/p/14030729.html