得到局域网内所有SQL服务器的服务名

using System;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;


namespace GetDBs
{
    public class SqlLocator
    {
        [DllImport(""odbc32.dll"")]
        private static extern short SQLAllocHandle(short hType, IntPtr inputHandle, out IntPtr outputHandle);
        [DllImport(""odbc32.dll"")]
        private static extern short SQLSetEnvAttr(IntPtr henv, int attribute, IntPtr valuePtr, int strLength);
        [DllImport(""odbc32.dll"")]
        private static extern short SQLFreeHandle(short hType, IntPtr handle); 
        [DllImport(""odbc32.dll"",CharSet=CharSet.Ansi)]
        private static extern short SQLBrowseConnect(IntPtr hconn, StringBuilder inString, 
            short inStringLength, StringBuilder outString, short outStringLength,
            out short outLengthNeeded);

        private const short SQL_HANDLE_ENV = 1;
        private const short SQL_HANDLE_DBC = 2;
        private const int SQL_ATTR_ODBC_VERSION = 200;
        private const int SQL_OV_ODBC3 = 3;
        private const short SQL_SUCCESS = 0;
        
        private const short SQL_NEED_DATA = 99;
        private const short DEFAULT_RESULT_SIZE = 1024;
        //private const string SQL_DRIVER_STR = ""DRIVER=ORACLE ODBC DRIVER"";
        private const string SQL_DRIVER_STR = ""DRIVER=SQL SERVER"";
    
        private SqlLocator(){}
/**//// <summary>
/// µΓµ½ΝψΒηΔΪΛωΣΠµΔΜαΉ©SQL·ώΞρµΔ·ώΞρΓϋ
/// </summary>
/// <returns></returns>
        public static string[] GetServers()
        {
            string[] retval = null;
            string txt = string.Empty;
            IntPtr henv = IntPtr.Zero;
            IntPtr hconn = IntPtr.Zero;
            StringBuilder inString = new StringBuilder(SQL_DRIVER_STR);
            StringBuilder outString = new StringBuilder(DEFAULT_RESULT_SIZE);
            short inStringLength = (short) inString.Length;
            short lenNeeded = 0;

            try
            {
                if (SQL_SUCCESS == SQLAllocHandle(SQL_HANDLE_ENV, henv, out henv))
                {
                    if (SQL_SUCCESS == SQLSetEnvAttr(henv,SQL_ATTR_ODBC_VERSION,(IntPtr)SQL_OV_ODBC3,0))
                    {
                        if (SQL_SUCCESS == SQLAllocHandle(SQL_HANDLE_DBC, henv, out hconn))
                        {
                            if (SQL_NEED_DATA ==  SQLBrowseConnect(hconn, inString, inStringLength, outString, 
                                DEFAULT_RESULT_SIZE, out lenNeeded))
                            {
                                if (DEFAULT_RESULT_SIZE < lenNeeded)
                                {
                                    outString.Capacity = lenNeeded;
                                    if (SQL_NEED_DATA != SQLBrowseConnect(hconn, inString, inStringLength, outString, 
                                        lenNeeded,out lenNeeded))
                                    {
                                        throw new ApplicationException(""Unabled to aquire SQL Servers from ODBC driver."");
                                    }    
                                }
                                txt = outString.ToString();
                                int start = txt.IndexOf(""{"") + 1;
                                int len = txt.IndexOf(""}"") - start;
                                if ((start > 0) && (len > 0))
                                {
                                    txt = txt.Substring(start,len);
                                }
                                else
                                {
                                    txt = string.Empty;
                                }
                            }                        
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                //Throw away any error if we are not in debug mode
#if (DEBUG)
                MessageBox.Show(ex.Message,""Acquire SQL Servier List Error"");
#endif 
                txt = string.Empty;
            }
            finally
            {
                if (hconn != IntPtr.Zero)
                {
                    SQLFreeHandle(SQL_HANDLE_DBC,hconn);
                }
                if (henv != IntPtr.Zero)
                {
                    SQLFreeHandle(SQL_HANDLE_ENV,hconn);
                }
            }
    
            if (txt.Length > 0)
            {
                retval = txt.Split("","".ToCharArray());
            }

            return retval;
        }
    }
}