this.lstViewEventDetail.Items.Clear();
string selectedItem = this.lstBoxCtrlEventType.SelectedItem.ToString().Trim();
            EventLog[] eventLogs = EventLog.GetEventLogs();
foreach (EventLog evntLg in eventLogs)
            {
if (selectedItem==evntLg.LogDisplayName)
               {
                   selectedItem = evntLg.Log;
break;
               }
            }

if (EventLog.Exists(selectedItem))
            {
                EventLog selectedLog = new EventLog();
                selectedLog.Log = selectedItem;
int i = 0;
foreach (EventLogEntry selectedEntry in selectedLog.Entries)
                {
                    ListViewItem lvi = new ListViewItem();
                    lvi.SubItems.Clear();
                    lvi.SubItems[0].Text = selectedEntry.EntryType.ToString();
                    lvi.SubItems.Add(selectedEntry.TimeWritten.Date.ToString("yyyy-MM-dd"));
                    lvi.SubItems.Add(selectedEntry.TimeWritten.TimeOfDay.ToString());
                    lvi.SubItems.Add(selectedEntry.Source);
string category = selectedEntry.Category;
if (category=="(0)")
                    {
                        category = "NONE";
                    }
                    lvi.SubItems.Add(category);
                    lvi.SubItems.Add(selectedEntry.InstanceId.ToString());
string usrName = selectedEntry.UserName;
if (usrName==null)
                    {
                        usrName = "N/A";
                    }
                    lvi.SubItems.Add(usrName);
                    lvi.SubItems.Add(selectedEntry.MachineName);
this.lstViewEventDetail.Items.Add(lvi);
                    i++;
if (i > 300)
                    {
break;
                    }
                }
//selectedLog.Clear();
            }

        private void btnCheck_Click(object sender, EventArgs e)
        {
            string ipAddress = this.cboBoxIp.Text.Trim();
            Regex rgx = new Regex(@"^([1-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(\.([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3}$");
            if (rgx.IsMatch(ipAddress))
            {
                this.labelIpResult.Text = GetName(ipAddress);
                this.labelMacResult.Text = GetMacAddress(ipAddress);
            }
            else
            {
                this.labelIpResult.Text = "IP address is not valid.";
                this.labelMacResult.Text = "No mac result";
            }
        }

        ///<summary>
        /// 得到所有局域网内机器名
        ///</summary>
        private void GetAllLocalMachineName()
        {
            System.Diagnostics.ProcessStartInfo prcssStrtInfo = new System.Diagnostics.ProcessStartInfo();
            prcssStrtInfo.FileName = @"C:\windows\system32\cmd.exe";
            prcssStrtInfo.Arguments = @"/c net view > F:\\LanMachineName.txt"; // 将所有局域网机器名输出到文本文件
            prcssStrtInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
            System.Diagnostics.Process.Start(prcssStrtInfo);
        }

        ///<summary>
        /// 通过Ip地址获得主机名
        ///</summary>
        ///<param name="IpAddress"></param>
        ///<returns></returns>
        private string GetName(string IpAddress)//获取指定IP的计算机名称
        {
            string name="";
            try
            {
                IPHostEntry ipHstEntry = Dns.GetHostByAddress(IpAddress);//传递IP地址\
                //IPHostEntry ipHstEntry = Dns.GetHostEntry(IpAddress);
                name = ipHstEntry.HostName.ToString();//取得主机名
            }
            catch (Exception e)
            {
                name = e.Message;
            }
            return name;
        }

        ///<summary>
        /// 通过Ip得到MAC地址
        ///</summary>
        ///<param name="IpAddress"></param>
        ///<returns></returns>
        private string GetMacAddress(string IpAddress)//得到指定IP的MAC地址
        {
            string macAddress = "";
            Int32 ldest = 0;
            try
            {
                ldest = inet_addr(IpAddress);
            }
            catch (Exception iperr)
            {
                MessageBox.Show(iperr.Message);
            }
            Int64 macinfo = new Int64();
            Int32 len = 6;
            try
            {
                int res = SendARP(ldest, 0, ref macinfo, ref len);
            }
            catch (Exception err)
            {
                //    throw new Exception("在解析MAC地址过程发生了错误!"); 
                MessageBox.Show(err.Message);
            }
            string originalMACAddress = macinfo.ToString("X4");
            if (originalMACAddress != "0000" && originalMACAddress.Length == 12)
            { //合法MAC地址 
                string mac1, mac2, mac3, mac4, mac5, mac6;
                mac1 = originalMACAddress.Substring(10, 2);
                mac2 = originalMACAddress.Substring(8, 2);
                mac3 = originalMACAddress.Substring(6, 2);
                mac4 = originalMACAddress.Substring(4, 2);
                mac5 = originalMACAddress.Substring(2, 2);
                mac6 = originalMACAddress.Substring(0, 2);
                macAddress = mac1 + ":" + mac2 + ":" + mac3 + ":" + mac4 + ":" + mac5 + ":" + mac6;
                //canPing = true;
            }
            else
            {
                macAddress = "无法探测到MAC地址";
                //canPing = false;
            }
            return macAddress;
        }