远程dll注入 C#

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Drawing;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Windows.Forms;

namespace hooktest01
{
    public partial class Form1 : Form
    {
        [DllImport("kernel32.dll")]
        public static extern int VirtualAllocEx(IntPtr hwnd, Int32 lpaddress, int size, int type, Int32 tect);
        [DllImport("kernel32.dll")]
        public static extern Boolean WriteProcessMemory(IntPtr hwnd, int baseaddress, string buffer, int nsize, int filewriten);
        [DllImport("kernel32.dll")]
        public static extern int GetProcAddress(int hwnd, string lpname);
        [DllImport("kernel32.dll")]
        public static extern int GetModuleHandleA(string name);
        [DllImport("kernel32.dll")]
        public static extern IntPtr CreateRemoteThread(IntPtr hwnd, int attrib, int size, int address, int par, int flags, int threadid);
        [DllImport("kernel32.dll")]
        public static extern Int32 WaitForSingleObject(IntPtr hHandle, UInt32 dwMilliseconds);
        [DllImport("kernel32.dll")]
        public static extern Boolean VirtualFree(IntPtr lpAddress, Int32 dwSize, Int32 dwFreeType);
        Process pname;
        UInt32 INFINITE = 0xFFFFFFFF;
        Int32 PAGE_EXECUTE_READWRITE = 0x40;
        Int32 MEM_COMMIT = 0x1000;
        Int32 MEM_RESERVE = 0x2000;
        Int32 MEM_RELEASE = 0x8000;
        Int32 AllocBaseAddress;
        IntPtr hwnd;
        string dllname;
        Int32 Pid;
        Boolean ok;
        Int32 loadaddr;
        IntPtr ThreadHwnd;


        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                if (textBox1.Text == "" || textBox1.Text == null)
                {
                    MessageBox.Show("Pid is null"); return;
                }
                if (textBox2.Text == "" || textBox2.Text == null)
                {
                    MessageBox.Show("dll name is null"); return;
                }
                Pid = Int32.Parse(textBox1.Text);
                dllname = textBox2.Text;
            }
            catch(Exception error)
            {
                MessageBox.Show(error.Message); return;
            }
            try
            {
                pname = Process.GetProcessById(Pid);
                hwnd = pname.Handle;
            }
            catch(Exception error)
            {   //当标示pid的进程不存在时发生异常；
                MessageBox.Show (error.Message); return;
            }
            AllocBaseAddress= VirtualAllocEx(hwnd, 0, dllname.Length + 1, MEM_COMMIT+ MEM_RESERVE, PAGE_EXECUTE_READWRITE);
            if (AllocBaseAddress == 0)
            {
                MessageBox.Show("virtualallocex  fail"); return;
            }
            ok=WriteProcessMemory(hwnd, AllocBaseAddress, dllname, dllname.Length + 1,0);
            if (!ok)
            {
                MessageBox.Show("writeprocessmemory fail"); return;
            }
            loadaddr = GetProcAddress(GetModuleHandleA("kernel32.dll"), "LoadLibraryA");
            if (loadaddr == 0)
            {   //取得LoadLibraryA的地址失败时返回
                MessageBox.Show("get loadlibraryA fail"); return;
            }
            ThreadHwnd=CreateRemoteThread(hwnd, 0, 0, loadaddr, AllocBaseAddress,0, 0);
            if (ThreadHwnd ==IntPtr.Zero)
            {
                MessageBox.Show("createremotethread fail"); return;
            }
           
            
            WaitForSingleObject(ThreadHwnd, INFINITE);
            MessageBox.Show("ok ,you can check now!!!");
            VirtualFree(hwnd, 0, MEM_RELEASE);
            //下面开始枚举模块列表；
            ProcessModuleCollection pmodule = pname.Modules;
            foreach (ProcessModule processm in pmodule)
            {
                listBox1.Items.Add(processm.FileName);
            }
            pname.Dispose();
        }
        //进程 句柄

    }
}

 转自：http://blog.csdn.net/pandyer/archive/2009/01/06/3719836.aspx