获取应用程序进程实例,

/// <summary>
        /// 获取应用程序进程实例,如果没有匹配进程，返回Null
        /// </summary>
        /// <returns>返回当前Process实例</returns>
        public static Process GetRunningInstance()
        {           

            Process currentProcess = Process.GetCurrentProcess();//获取当前进程
            //获取当前运行程序完全限定名
            string currentFileName = currentProcess.MainModule.FileName;
            //获取进程名为ProcessName的Process数组。
            Process[] processes = Process.GetProcessesByName(currentProcess.ProcessName);
            //遍历有相同进程名称正在运行的进程
            foreach (Process process in processes)
            {
                if (process.MainModule.FileName == currentFileName)
                {
                    if (process.Id != currentProcess.Id)//根据进程ID排除当前进程
                         return process;//返回已运行的进程实例
                }
            }
            return null;
        }