C#创建只显示文字的透明窗体

【核心代码】

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace Image
{
	/// <summary>
	/// Form1 的摘要说明。
	/// </summary>
	public class Form1 : System.Windows.Forms.Form
	{
		/// <summary>
		/// 必需的设计器变量。
		/// </summary>
		private System.ComponentModel.Container components = null;

		public Form1()
		{
			//
			// Windows 窗体设计器支持所必需的
			//
			InitializeComponent();

			//
			// TODO: 在 InitializeComponent 调用后添加任何构造函数代码
			//
		}

		/// <summary>
		/// 清理所有正在使用的资源。
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if (components != null) 
				{
					components.Dispose();
				}
			}
			base.Dispose( disposing );
		}

		#region Windows 窗体设计器生成的代码
		/// <summary>
		/// 设计器支持所需的方法 - 不要使用代码编辑器修改
		/// 此方法的内容。
		/// </summary>
		private void InitializeComponent()
		{
            this.SuspendLayout();
            // 
            // Form1
            // 
            this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
            this.BackColor = System.Drawing.Color.Yellow;
            this.ClientSize = new System.Drawing.Size(368, 281);
            this.MaximizeBox = false;
            this.Name = "Form1";
            this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
            this.Text = "演示创建文字形窗体";
            this.Paint  = new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);
            this.MouseUp  = new System.Windows.Forms.MouseEventHandler(this.Form1_MouseUp);
            this.Load  = new System.EventHandler(this.Form1_Load);
            this.ResumeLayout(false);

		}
		#endregion

		/// <summary>
		/// 应用程序的主入口点。
        ///// </summary>
        [STAThread]
        static void Main()
        {
            Application.Run(new Form1());
        }
        [System.Runtime.InteropServices.DllImport("gdi32")]
        private static extern IntPtr CreateFont(int H, int W, int E, int O, int FW, int I, int u, int S, int C, int OP, int CP, int Q, int PAF, string F);
        [System.Runtime.InteropServices.DllImport("user32")]
        private static extern IntPtr GetDC(IntPtr hwnd);
        [System.Runtime.InteropServices.DllImport("gdi32")]
        private static extern IntPtr BeginPath(IntPtr hdc);
        [System.Runtime.InteropServices.DllImport("gdi32")]
        private static extern IntPtr EndPath(IntPtr hdc);
        [System.Runtime.InteropServices.DllImport("gdi32")]
        private static extern IntPtr PathToRegion(IntPtr hdc);
        [System.Runtime.InteropServices.DllImport("gdi32")]
        private static extern int SetBkMode(IntPtr hdc, int nBkMode);
        [System.Runtime.InteropServices.DllImport("gdi32")]
        private static extern IntPtr SelectObject(IntPtr hdc, IntPtr hObject);
        [System.Runtime.InteropServices.DllImport("gdi32")]
        private static extern int TextOut(IntPtr hdc, int x, int y, string lpString, int nCount);
        [System.Runtime.InteropServices.DllImport("user32")]
        private static extern IntPtr SetWindowRgn(IntPtr hwnd, IntPtr hRgn, bool bRedraw);

		private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
		{
			//创建新字体
			IntPtr MyFont=CreateFont(160,100,0,0,0,0,0,0,0,0,0,0,0,"宋体_GB2312");
			//取得设备句柄
			IntPtr MyDC=GetDC(this.Handle);
			//设置背景模式
			SetBkMode(MyDC,1);
			//开始记录轮廓路径
			BeginPath(MyDC);
			//设置文字输出字体
			IntPtr MyOldFont=SelectObject(MyDC,MyFont);
			//输出文字
			TextOut(MyDC,0,20,"小胖",4);
			//恢复原始字体对象
			SelectObject(MyDC,MyOldFont);
			//结束记录轮廓路径绘制
			EndPath(MyDC);
			//创建文字区域
			IntPtr MyRgn=PathToRegion(MyDC);
			//使用文字区域创建程序窗体
			SetWindowRgn(this.Handle,MyRgn,true);
		}

		private void Form1_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
		{//关闭程序
		   this.Close();
		}

        private void Form1_Load(object sender, EventArgs e)
        {

        }	
	}
}