获取SQL Server服务器列表的几种方法
一、 SQL DMO
描述：SQL Distributed Management Objects（SQL分布式管理对象），存在于SQLDMO.dll文件中，实际上是一个COM 对象，通过调用SQL DMO的ListAvailableSQLServers方法取得。
列表类型：列举装有“客户端”和“服务端”的计算机。
适用条件：装有 SQL Server，且有SQLDMO.dll文件。
速度：中
调用示例：GetSQLServerList(ListBox1.items);
代码：
uses
ComObj;
function GetSQLServerList(var AList: TStrings): Boolean;
var
SQLServerApp: Variant;
ServerList: Variant;
i: Integer;
begin
Result := True;
try
SQLServerApp := CreateOleObject('SQLDMO.Application');
ServerList := SQLServerApp.ListAvailableSQLServers;
for i := 1 to ServerList.Count do
AList.Add(ServerList.Item(i));
SQLServerApp := Unassigned;
ServerList := Unassigned;
except
Result := False;
end;
end;
二、 NetServerEnum
描述：网络服务函数，存在于NetApi32.dll文件中；通过NetServerEnum函数可取得装有SQL Server服务端的计算机列表，只装有SQL Server客户端的计算机将不会被列举其中；如果一台计算机的SQL Server服务刚刚启动，那么此函数将会过很久才能取到该计算机。
列表类型：仅列举装有“服务端”的计算机。
适用条件：有NetApi32.dll文件。
速度：快
调用示例：GetSQLServerList(ListBox1.items);
代码：
type
NET_API_STATUS = DWORD;
PServerInfo100 = ^TServerInfo100;
_SERVER_INFO_100 = record
sv100_platform_id: DWORD;
sv100_name: LPWSTR;
end;
{$EXTERNALSYM _SERVER_INFO_100}
TServerInfo100 = _SERVER_INFO_100;
SERVER_INFO_100 = _SERVER_INFO_100;
{$EXTERNALSYM SERVER_INFO_100}
const
NERR_Success = 0;
MAX_PREFERRED_LENGTH = DWORD(-1);
SV_TYPE_SQLSERVER = $00000004;
function NetApiBufferAllocate(ByteCount: DWORD; var Buffer: Pointer):
NET_API_STATUS; stdcall; external 'netapi32.dll' name 'NetApiBufferAllocate';
function NetServerEnum(ServerName: LPCWSTR; Level: DWORD; var BufPtr: Pointer;
PrefMaxLen: DWORD; var EntriesRead: DWORD; var TotalEntries: DWORD;
ServerType: DWORD; Domain: LPCWSTR; ResumeHandle: PDWORD): NET_API_STATUS;
stdcall; external 'netapi32.dll' name 'NetServerEnum';
function NetApiBufferFree(Buffer: Pointer): NET_API_STATUS; stdcall; external
'netapi32.dll' name 'NetApiBufferFree';
function GetSQLServerList(var AList: TStrings; pwcServerName: PWChar = nil;
pwcDomain: PWChar = nil): Boolean;
var
NetAPIStatus: DWORD;
dwLevel: DWORD;
pReturnSvrInfo: Pointer;
dwPrefMaxLen: DWORD;
dwEntriesRead: DWORD;
dwTotalEntries: DWORD;
dwServerType: DWORD;
dwResumeHandle: PDWORD;
pCurSvrInfo: PServerInfo100;
i, j: Integer;
begin
Result := True;
try
dwLevel := 100;
pReturnSvrInfo := nil;
dwPrefMaxLen := MAX_PREFERRED_LENGTH;
dwEntriesRead := 0;
dwTotalEntries := 0;
dwServerType := SV_TYPE_SQLSERVER; //服务器类型
dwResumeHandle := nil;
NetApiBufferAllocate(SizeOf(pReturnSvrInfo), pReturnSvrInfo);
try
NetAPIStatus := NetServerEnum(pwcServerName, dwLevel, pReturnSvrInfo,
dwPrefMaxLen, dwEntriesRead, dwTotalEntries, dwServerType, pwcDomain,
dwResumeHandle);
if ((NetAPIStatus = NERR_Success) or (NetAPIStatus = ERROR_MORE_DATA)) and
(pReturnSvrInfo <> nil) then
begin
pCurSvrInfo := pReturnSvrInfo;
// 循环取得所有SQL Server服务器
i := 0;
j := dwEntriesRead;
while i < j do
begin
if pCurSvrInfo = nil then
Break;
with AList do
Add(pCurSvrInfo^.sv100_name);
Inc(i);
Inc(pCurSvrInfo);
end;
end;
finally
if Assigned(pReturnSvrInfo) then
NetApiBufferFree(pReturnSvrInfo);
end;
except
Result := False;
end;
end;
三、 SQLBrowseConnect
描述：ODBC函数（Microsoft Open Database Connectivity，开放式数据库连接），存在于odbc32.dll文件中；通过SQLBrowseConnect函数可返回连接字符串信息，包括DSN、DRIVER、SERVER、UID、PWD、APP、WSID、DATABASE、LANGUAGE等信息。在函数GetODBCInfo 中传入itServer、itDatabase、itLanguage可分别取得“服务器”、“数据库”及“语言”等信息列表，其中itDatabase、itLanguage默认取本地信息，取远程信息请自行修改“'Driver={SQL Server};SERVER=(local);UID=sa;PWD='”连接字符串。
列表类型：列举装有“客户端”和“服务端”的计算机。
适用条件：由于MDAC 2.6 、2.6 SP1、2.7和Microsoft ODBC Driver for SQL Server 2000 2000.80.194有Bug，因此在这些版本中此函数无法取得Microsoft SQL Server 7.0的服务器。
速度：中
调用示例：GetODBCInfo(ListBox1.items, itServer);
代码：
type
TInfoType = (itServer, itDatabase, itLanguage);
SQLHANDLE = Pointer;
SQLSMALLINT = SHORT;
SQLINTEGER = LongInt;
PSQLHANDLE = ^SQLHANDLE;
SQLHENV = SQLHANDLE;
SQLHDBC = SQLHANDLE;
SQLRETURN = SQLSMALLINT;
SQLCHAR = UCHAR;
PSQLCHAR = ^SQLCHAR;
SQLPOINTER = Pointer;
PSQLSMALLINT = ^SQLSMALLINT;
function SQLAllocHandle(HandleType: SQLSMALLINT; InputHandle: SQLHANDLE;
OutputHandle: PSQLHANDLE): SQLRETURN; stdcall; external 'odbc32.dll' name
'SQLAllocHandle';
function SQLSetEnvAttr(EnvironmentHandle: SQLHENV; Attribute: SQLINTEGER;
Value: SQLPOINTER; StringLength: SQLINTEGER): SQLRETURN; stdcall; external
'odbc32.dll' name 'SQLSetEnvAttr';
function SQLBrowseConnect(hdbc: SQLHDBC; szConnStrIn: PSQLCHAR;
cbConnStrIn: SQLSMALLINT; szConnStrOut: PSQLCHAR;
cbConnStrOutMax: SQLSMALLINT; pcbConnStrOut: PSQLSMALLINT): SQLRETURN;
stdcall; external 'odbc32.dll' name 'SQLBrowseConnect';
function SQLDisconnect(ConnectionHandle: SQLHDBC): SQLRETURN; stdcall; external
'odbc32.dll' name 'SQLDisconnect';
function SQLFreeHandle(HandleType: SQLSMALLINT; Handle: SQLHANDLE): SQLRETURN;
stdcall; external 'odbc32.dll' name 'SQLFreeHandle';
const
SQL_HANDLE_ENV = 1;
SQL_HANDLE_DBC = 2;
SQL_NULL_HANDLE = LongInt(0);
SQL_SUCCESS = 0;
SQL_ERROR = -1;
SQL_ATTR_ODBC_VERSION = 200;
SQL_OV_ODBC3 = ULONG(3);
SQL_NTS = -3;
function GetODBCInfo(var AList: TStrings; InfoType: TInfoType): Boolean;
const
ConnStrOutMax = 4824;
SplitterStr = '={';
var
HENV: SQLHENV;
HDBC: SQLHDBC;
RetCode: SQLRETURN;
ConnStrOut: PSQLCHAR;
cbConnStrOut: SQLSMALLINT;
ConnStrIn, TmpStr: string;
TmpPos: Integer;
begin
case InfoType of
itServer: ConnStrIn := 'Driver={SQL Server}';
itDatabase, itLanguage: ConnStrIn := 'Driver={SQL Server};SERVER=(local);UID=sa;PWD=';
end;
Result := False;
try
// 分配 ODBC 环境句柄
RetCode := SQLAllocHandle(SQL_HANDLE_ENV, SQLPOINTER(SQL_NULL_HANDLE), @HENV);
if RetCode = SQL_ERROR then
Exit;
// 设置 ODBC 版本
RetCode := SQLSetEnvAttr(HENV, SQL_ATTR_ODBC_VERSION, SQLPointer(SQL_OV_ODBC3), 0);
if RetCode <> SQL_SUCCESS then
Exit;
// 分配数据库连接句柄
RetCode := SQLAllocHandle(SQL_HANDLE_DBC, HENV, @HDBC);
if RetCode <> SQL_SUCCESS then
Exit;
GetMem(ConnStrOut, ConnStrOutMax);
RetCode := SQLBrowseConnect(HDBC, PSQLCHAR(ConnStrIn), SQL_NTS, ConnStrOut,
ConnStrOutMax, @cbConnStrOut);
if RetCode <> SQL_ERROR then
begin
TmpStr := PChar(ConnStrOut);
if InfoType = itLanguage then
Delete(TmpStr, 1, AnsiPos('};', TmpStr) + 1);
Delete(TmpStr, 1, AnsiPos(SplitterStr, TmpStr) + 1);
Delete(TmpStr, AnsiPos('}', TmpStr), Length(TmpStr));
while TmpStr <> '' do
begin
TmpPos := AnsiPos(',', TmpStr);
if TmpPos > 0 then
AList.Add(Copy(TmpStr, 1, TmpPos - 1))
else
begin
AList.Add(TmpStr);
TmpStr := '';
end;
Delete(TmpStr, 1, TmpPos)
end;
Result := True;
end;
FreeMem(ConnStrOut, ConnStrOutMax);
finally
if Assigned(HDBC) then
begin
SQLDisconnect(HDBC);
SQLFreeHandle(SQL_HANDLE_DBC, HDBC);
HDBC := nil;
end;
if Assigned(HENV) then
begin
SQLFreeHandle(SQL_HANDLE_ENV, HENV);
HENV := nil;
end;
end;
end;
张伟(Alan) Alan@cnvcl.org
