BatteryIndicator/BatteryIndicator/Program.cs

using BatteryIndicator.Views;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace BatteryIndicator
{
    static class Program
    {
        public static List<Form> formList = new List<Form>();
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Process instance = RunningInstance();
            if (instance == null)
            {

                Application.EnableVisualStyles();
                Application.SetCompatibleTextRenderingDefault(false);
                //Application.Run(new SettingForm());

                TrayIcon trayIcon = new TrayIcon();
                Application.Run();
            }
            else
            {
               // MessageBox.Show("程序已经在运行", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }

        }

        [DllImport("User32.dll", EntryPoint = "FindWindow")]
        private static extern IntPtr FindWindow(string lpClassName, string lpWindowName);

        [DllImport("User32.dll")]
        private static extern bool ShowWindowAsync(IntPtr hWnd, int cmdShow);

        [DllImport("User32.dll")]
        private static extern bool SetForegroundWindow(IntPtr hWnd);

        public static Process RunningInstance()
        {
            // 获取当前活动的进程
            Process current = Process.GetCurrentProcess();
            // 获取当前本地计算机上指定的进程名称的所有进程
            Process[] processes = Process.GetProcessesByName(current.ProcessName);
            foreach (Process process in processes)
            {
                // 忽略当前进程
                if (process.Id != current.Id)
                {
                    if (Assembly.GetExecutingAssembly().Location.Replace("/", "\\") == current.MainModule.FileName)
                    {
                        return process;
                    }
                }
            }

            // 如果没有其他同名进程存在,则返回 null
            return null;
        }
        /// <summary>
        /// new a Form object
        /// </summary>
        /// <param name="type"></param>
        /// <returns></returns>
        internal static Form getInstance(Type type) {
            Form form = null;
            foreach(Form formItem in Program.formList)
            {
                if (form.GetType() == type)
                {
                    form = formItem;
                    form.Activate();

                }
                else if (form == null)
                {
                    object obj = Activator.CreateInstance(type);
                    if (obj is Form)
                    {
                        form = obj as Form;
                        form.Show();
                    }
                }
            }
            return form;
        }
    }
}