声明：private Point mouseOffset; //记录鼠标指针的坐标
private bool isMouseDown = false; //记录鼠标按键是否按下
调用 ： BLL.BitmapRegion.CreateControlRegion(this, new Bitmap(Application.StartupPath + "\\pic\\login.bmp"));
相关方法：
#region MouseDown事件
private void form1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
{
int xOffset;
int yOffset;
if (e.Button == MouseButtons.Left)
{
xOffset = -e.X;// -SystemInformation.FrameBorderSize.Width;
yOffset = -e.Y;// -SystemInformation.FrameBorderSize.Height;
mouseOffset = new Point(xOffset, yOffset);
isMouseDown = true;
}
}
#endregion
#region MouseMove事件
private void form1_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
{
if (isMouseDown)
{
Point mousePos = Control.MousePosition;
mousePos.Offset(mouseOffset.X, mouseOffset.Y);
Location = mousePos;
}
}
#endregion
#region MouseUp事件
private void form1_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
{
// 修改鼠标状态isMouseDown的值
// 确保只有鼠标左键按下并移动时，才移动窗体
if (e.Button == MouseButtons.Left)
{
isMouseDown = false;
}
}
#endregion
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;
namespace BLL
{
/// <summary>
/// Summary description for BitmapRegion.
/// </summary>
public class BitmapRegion
{
public BitmapRegion()
{ }
/// <summary>
/// Create and apply the region on the supplied control
/// 创建支持位图区域的控件（目前有button和form）
/// </summary>
/// <param name="control">The Control object to apply the region to控件</param>
/// <param name="bitmap">The Bitmap object to create the region from位图</param>
public static void CreateControlRegion(Control control, Bitmap bitmap)
{
// Return if control and bitmap are null
//判断是否存在控件和位图
if (control == null || bitmap == null)
return;
// Set our control''s size to be the same as the bitmap
//设置控件大小为位图大小
control.Width = bitmap.Width;
control.Height = bitmap.Height;
// Check if we are dealing with Form here
//当控件是form时
if (control is System.Windows.Forms.Form)
{
// Cast to a Form object
//强制转换为FORM
Form form = (Form)control;
// Set our form''s size to be a little larger that the bitmap just
// in case the form''s border style is not set to none in the first place
//当FORM的边界FormBorderStyle不为NONE时，应将FORM的大小设置成比位图大小稍大一点
form.Width = control.Width;
form.Height = control.Height;
// No border
//没有边界
form.FormBorderStyle = FormBorderStyle.None;
// Set bitmap as the background image
//将位图设置成窗体背景图片
form.BackgroundImage = bitmap;
// Calculate the graphics path based on the bitmap supplied
//计算位图中不透明部分的边界
GraphicsPath graphicsPath = CalculateControlGraphicsPath(bitmap);
// Apply new region
//应用新的区域
form.Region = new Region(graphicsPath);
}
// Check if we are dealing with Button here
//当控件是button时
else if (control is System.Windows.Forms.Button)
{
// Cast to a button object
//强制转换为 button
Button button = (Button)control;
// Do not show button text
//不显示button text
button.Text = "";
// Change cursor to hand when over button
//改变 cursor的style
button.Cursor = Cursors.Hand;
// Set background image of button
//设置button的背景图片
button.BackgroundImage = bitmap;
// Calculate the graphics path based on the bitmap supplied
//计算位图中不透明部分的边界
GraphicsPath graphicsPath = CalculateControlGraphicsPath(bitmap);
// Apply new region
//应用新的区域
button.Region = new Region(graphicsPath);
}
}
/// <summary>
/// Calculate the graphics path that representing the figure in the bitmap
/// excluding the transparent color which is the top left pixel.
/// //计算位图中不透明部分的边界
/// </summary>
/// <param name="bitmap">The Bitmap object to calculate our graphics path from</param>
/// <returns>Calculated graphics path</returns>
private static GraphicsPath CalculateControlGraphicsPath(Bitmap bitmap)
{
// Create GraphicsPath for our bitmap calculation
//创建 GraphicsPath
GraphicsPath graphicsPath = new GraphicsPath();
// Use the top left pixel as our transparent color
//使用左上角的一点的颜色作为我们透明色
Color colorTransparent = bitmap.GetPixel(0, 0);
// This is to store the column value where an opaque pixel is first found.
// This value will determine where we start scanning for trailing opaque pixels.
//第一个找到点的X
int colOpaquePixel = 0;
// Go through all rows (Y axis)
// 偏历所有行（Y方向）
for (int row = 0; row < bitmap.Height; row++)
{
// Reset value
//重设
colOpaquePixel = 0;
// Go through all columns (X axis)
//偏历所有列（X方向）
for (int col = 0; col < bitmap.Width; col++)
{
// If this is an opaque pixel, mark it and search for anymore trailing behind
//如果是不需要透明处理的点则标记，然后继续偏历
if (bitmap.GetPixel(col, row) != colorTransparent)
{
// Opaque pixel found, mark current position
//记录当前
colOpaquePixel = col;
// Create another variable to set the current pixel position
//建立新变量来记录当前点
int colNext = col;
// Starting from current found opaque pixel, search for anymore opaque pixels
// trailing behind, until a transparent pixel is found or minimum width is reached
///从找到的不透明点开始，继续寻找不透明点,一直到找到或则达到图片宽度
for (colNext = colOpaquePixel; colNext < bitmap.Width; colNext++)
if (bitmap.GetPixel(colNext, row) == colorTransparent)
break;
// Form a rectangle for line of opaque pixels found and add it to our graphics path
//将不透明点加到graphics path
graphicsPath.AddRectangle(new Rectangle(colOpaquePixel, row, colNext - colOpaquePixel, 1));
// No need to scan the line of opaque pixels just found
col = colNext;
}
}
}
// Return calculated graphics path
return graphicsPath;
}
}
}