C# Winform 窗體美化（三、不規則窗體）
阿新 • • 發佈：2019-01-06
三、不規則窗體
概況
之前學習的 LayeredSkin 看到裡面有個異形視窗，比較感興趣，所以就找一下資料研究一下。不規則窗體學習有一個比較好的例子，叫 GoldFishProject，是一條魚金魚在螢幕上游。
現學習了兩種實現方式：
1. UpdateLayeredWindow
2. GraphicsPath
1.UpdateLayeredWindow
這種方式實現的不規則視窗很平滑，沒有鋸齒，可以帶半透明的效果，但是不在響應 paint 方法，繪製不了窗體上的控制元件，效果圖：
程式碼如下：
窗體程式碼：
public partial class UpdateLayeredWindowForm : Form
{
bool Win32API程式碼：（從金魚的例子中引用的程式碼）
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using System;
using System.Runtime.InteropServices;
/// <summary>
/// Wind32API
/// </summary>
internal class Win32
{
#region 訊息
public const int MF_REMOVE = 0x1000;
public const int SC_RESTORE = 0xF120; //還原
public const int SC_MOVE = 0xF010; //移動
public const int SC_SIZE = 0xF000; //大小
public const int SC_MINIMIZE = 0xF020; //最小化
public const int SC_MAXIMIZE = 0xF030; //最大化
public const int SC_CLOSE = 0xF060; //關閉
public const int WM_SYSCOMMAND = 0x0112;
public const int WM_COMMAND = 0x0111;
public const int GW_HWNDFIRST = 0;
public const int GW_HWNDLAST = 1;
public const int GW_HWNDNEXT = 2;
public const int GW_HWNDPREV = 3;
public const int GW_OWNER = 4;
public const int GW_CHILD = 5;
public const int WM_NCCALCSIZE = 0x83;
public const int WM_WINDOWPOSCHANGING = 0x46;
public const int WM_PAINT = 0xF;
public const int WM_CREATE = 0x1;
public const int WM_NCCREATE = 0x81;
public const int WM_NCPAINT = 0x85;
public const int WM_PRINT = 0x317;
public const int WM_DESTROY = 0x2;
public const int WM_SHOWWINDOW = 0x18;
public const int WM_SHARED_MENU = 0x1E2;
public const int HC_ACTION = 0;
public const int WH_CALLWNDPROC = 4;
public const int GWL_WNDPROC = -4;
public const int WS_SYSMENU = 0x80000;
public const int WS_SIZEBOX = 0x40000;
public const int WS_MAXIMIZEBOX = 0x10000;
public const int WS_MINIMIZEBOX = 0x20000;
#endregion
[StructLayout(LayoutKind.Sequential)]
public struct Size
{
public Int32 cx;
public Int32 cy;
public Size(Int32 x, Int32 y)
{
cx = x;
cy = y;
}
}
[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct BLENDFUNCTION
{
public byte BlendOp;
public byte BlendFlags;
public byte SourceConstantAlpha;
public byte AlphaFormat;
}
[StructLayout(LayoutKind.Sequential)]
public struct Point
{
public Int32 x;
public Int32 y;
public Point(Int32 x, Int32 y)
{
this.x = x;
this.y = y;
}
}
public const byte AC_SRC_OVER = 0;
public const Int32 ULW_ALPHA = 2;
public const byte AC_SRC_ALPHA = 1;
[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern IntPtr CreateCompatibleDC(IntPtr hDC);
[DllImport("user32.dll", ExactSpelling = true, SetLastError = true)]
public static extern IntPtr GetDC(IntPtr hWnd);
[DllImport("gdi32.dll", ExactSpelling = true)]
public static extern IntPtr SelectObject(IntPtr hDC, IntPtr hObj);
[DllImport("user32.dll", ExactSpelling = true)]
public static extern int ReleaseDC(IntPtr hWnd, IntPtr hDC);
[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern int DeleteDC(IntPtr hDC);
[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern int DeleteObject(IntPtr hObj);
[DllImport("user32.dll", ExactSpelling = true, SetLastError = true)]
public static extern int UpdateLayeredWindow(IntPtr hwnd, IntPtr hdcDst, ref Point pptDst, ref Size psize, IntPtr hdcSrc, ref Point pptSrc, Int32 crKey, ref BLENDFUNCTION pblend, Int32 dwFlags);
[DllImport("gdi32.dll", ExactSpelling = true, SetLastError = true)]
public static extern IntPtr ExtCreateRegion(IntPtr lpXform, uint nCount, IntPtr rgnData);
[DllImport("user32")]
public static extern int SendMessage(IntPtr hwnd, int msg, int wp, int lp);
}2.GraphicsPath
這種方式不能實現半透明效果，有鋸齒，好處是能顯示出控制元件，貼個效果圖感受下：
程式碼如下：
public partial class GraphicsPathForm : Form
{
public GraphicsPathForm()
{
InitializeComponent();
}
private void GraphicsPathForm_Load(object sender, EventArgs e)
{
TopMost = true;//設定為最頂層
FormBorderStyle = FormBorderStyle.None;//取消視窗邊框
this.Region = new Region(GetWindowRegion(new Bitmap(BackgroundImage)));//設定不規則窗體
FormMovableEvent();//設定拖動窗體移動
}
#region 設定不規則窗體
private GraphicsPath GetWindowRegion(Bitmap bitmap)
{
Color TempColor;
GraphicsPath gp = new GraphicsPath();
if (bitmap == null) return null;
for (int nX = 0; nX < bitmap.Width; nX++)
{
for (int nY = 0; nY < bitmap.Height; nY++)
{
TempColor = bitmap.GetPixel(nX, nY);
//if (TempColor.A != 0)//去掉完全透明區域
if (TempColor.A == 255)//保留完全不透明的區域
{
gp.AddRectangle(new Rectangle(nX, nY, 1, 1));
}
}
}
return gp;
}
#endregion
#region 無標題欄的視窗移動
private Point mouseOffset; //記錄滑鼠指標的座標
private bool isMouseDown = false; //記錄滑鼠按鍵是否按下
/// <summary>
/// 窗體移動監聽繫結
/// </summary>
private void FormMovableEvent()
{
//窗體移動
this.MouseDown += new MouseEventHandler(Frm_MouseDown);
this.MouseMove += new MouseEventHandler(Frm_MouseMove);
this.MouseUp += new MouseEventHandler(Frm_MouseUp);
}
/// <summary>
/// 窗體按下時
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void Frm_MouseDown(object sender, MouseEventArgs e)
{
int xOffset;
int yOffset;
//點選窗體時，記錄滑鼠位置，啟動移動
if (e.Button == MouseButtons.Left)
{
xOffset = -e.X;
yOffset = -e.Y;
mouseOffset = new Point(xOffset, yOffset);
isMouseDown = true;
}
}
/// <summary>
/// 窗體移動時
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void Frm_MouseMove(object sender, MouseEventArgs e)
{
if (isMouseDown)
{
//移動的位置計算
Point mousePos = Control.MousePosition;
mousePos.Offset(mouseOffset.X, mouseOffset.Y);
Location = mousePos;
}
}
/// <summary>
/// 窗體按下並釋放按鈕時
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void Frm_MouseUp(object sender, MouseEventArgs e)
{
// 修改滑鼠狀態isMouseDown的值
// 確保只有滑鼠左鍵按下並移動時，才移動窗體
if (e.Button == MouseButtons.Left)
{
//鬆開滑鼠時，停止移動
isMouseDown = false;
//Top高度小於0的時候，等於0
if (this.Top < 0)
{
this.Top = 0;
}
}
}
#endregion
}像第一種不能新增控制元件的方法要想實現顯示控制元件的話，下一個關鍵詞就是“雙層窗體”，使用兩層窗體來實現一個不規則窗體的效果，大致步驟如下：
底層是面板層，使用第一種方法；
上層是控制元件層，使用第二種方法。