foreach遍历实例化对象，并调用类里的步骤

foreach遍历实例化对象，并调用类里的方法
在用list插入实例化对象时，遇到一个问题无法解决，求帮忙~代码如下：

using System;

using System.Collections.Generic;

//using System.Linq;

using System.Text;

using System.Diagnostics;

using System.Runtime.InteropServices;

using System.Threading;




namespace GL

{


    public class CrPro

    {

        int id;

        [StructLayout(LayoutKind.Sequential)]

        public class SECURITY_ATTRIBUTES

        {

            public int nLength;

            public string lpSecurityDescriptor;

            public bool bInheritHandle;

        }


        [StructLayout(LayoutKind.Sequential)]

        public struct STARTUPINFO

        {

            public int cb;

            public string lpReserved;

            public string lpDesktop;

            public int lpTitle;

            public int dwX;

            public int dwY;

            public int dwXSize;

            public int dwYSize;

            public int dwXCountChars;

            public int dwYCountChars;

            public int dwFillAttribute;

            public int dwFlags;

            public int wShowWindow;

            public int cbReserved2;

            public byte lpReserved2;

            public IntPtr hStdInput;

            public IntPtr hStdOutput;

            public IntPtr hStdError;

        }


        [StructLayout(LayoutKind.Sequential)]

        public struct PROCESS_INFORMATION

        {

            public IntPtr hProcess;

            public IntPtr hThread;

            public int dwProcessId;

            public int dwThreadId;

        }


        [DllImport("Kernel32.dll", CharSet = CharSet.Ansi)]

        public static extern bool CreateProcess(StringBuilder lpApplicationName, StringBuilder lpCommandLine,

                                                                    SECURITY_ATTRIBUTES lpProcessAttributes,

                                                                    SECURITY_ATTRIBUTES lpThreadAttributes,

                                                                    bool bInheritHandles,

                                                                    int dwCreationFlags,