如何自动检查电脑是否已安装tcp/ip协议(50分)

我做了一个监控程序，运行时老是提示电脑没有安装tcp/ip协议，
但检查电脑其实已安装了该协议，并且网络连接完好，是不是我的winsock误
报？不知那位高手给我一段代码，谢谢

给你一些网络函数

unit netFun;

interface
uses
SysUtils
,Windows
,dialogs
,winsock
,Classes
,ComObj
,WinInet
,Variants;

//错误信息常量
const
C_Err_GetLocalIp = '获取本地ip失败';
C_Err_GetNameByIpAddr = '获取主机名失败';
C_Err_GetSQLServerList = '获取SQLServer服务器失败';
C_Err_GetUserResource = '获取共享资失败';
C_Err_GetGroupList = '获取所有工作组失败';
C_Err_GetGroupUsers = '获取工作组中所有计算机失败';
C_Err_GetNetList = '获取所有网络类型失败';
C_Err_CheckNet = '网络不通';
C_Err_CheckAttachNet = '未登入网络';
C_Err_InternetConnected ='没有上网';

C_Txt_CheckNetSuccess = '网络畅通';
C_Txt_CheckAttachNetSuccess = '已登入网络';
C_Txt_InternetConnected ='上网了';


//得到本机的局域网Ip地址
Function GetLocalIp(var LocalIp:string): Boolean;
//通过Ip返回机器名
Function GetNameByIPAddr(IPAddr: string; var MacName: string): Boolean ;
//获取网络中SQLServer列表
// Function GetSQLServerList(var List: Tstringlist): Boolean;
//获取网络中的所有网络类型
Function GetNetList(var List: Tstringlist): Boolean;
//获取网络中的工作组
Function GetGroupList(var List: TStringList): Boolean;
//获取工作组中所有计算机
Function GetUsers(GroupName: string; var List: TStringList): Boolean;
//获取网络中的资源
Function GetUserResource(IpAddr: string; var List: TStringList): Boolean;
//映射网络驱动器
Function NetAddConnection(NetPath: Pchar; PassWord: Pchar;LocalPath: Pchar): Boolean;
//检测网络状态
Function CheckNet(IpAddr:string): Boolean;
//检测机器是否登入网络
Function CheckMacAttachNet: Boolean;

//判断Ip协议有没有安装 这个函数有问题
Function IsIPInstalled : boolean;
//检测机器是否上网
Function InternetConnected: Boolean;

//关闭网络连接
function NetCloseAll:boolean;
implementation

{=================================================================
功 能: 检测机器是否登入网络
参 数: 无
返回值: 成功: True 失败: False
备 注:
版 本:
1.0 2002/10/03 09:55:00
=================================================================}
Function CheckMacAttachNet: Boolean;
begin
Result := False;
if GetSystemMetrics(SM_NETWORK) <> 0 then
Result := True;
end;

{=================================================================
功 能: 返回本机的局域网Ip地址
参 数: 无
返回值: 成功: True, 并填充LocalIp 失败: False
备 注:
版 本:
1.0 2002/10/02 21:05:00
=================================================================}
function GetLocalIP(var LocalIp: string): Boolean;
var
HostEnt: PHostEnt;
Ip: string;
addr: pchar;
Buffer: array [0..63] of char;
GInitData: TWSADATA;
begin
Result := False;
try
WSAStartup(2, GInitData);
GetHostName(Buffer, SizeOf(Buffer));
HostEnt := GetHostByName(buffer);
if HostEnt = nil then Exit;
addr := HostEnt^.h_addr_list^;
ip := Format('%d.%d.%d.%d', [byte(addr [0]),
byte (addr [1]), byte (addr [2]), byte (addr [3])]);
LocalIp := Ip;
Result := True;
finally
WSACleanup;
end;
end;

{=================================================================
功 能: 通过Ip返回机器名
参 数:
IpAddr: 想要得到名字的Ip
返回值: 成功: 机器名 失败: ''
备 注:
inet_addr function converts a string containing an Internet
Protocol dotted address into an in_addr.
版 本:
1.0 2002/10/02 22:09:00
=================================================================}
function GetNameByIPAddr(IPAddr : String;var MacName:String): Boolean;
var
SockAddrIn: TSockAddrIn;
HostEnt: PHostEnt;
WSAData: TWSAData;
begin
Result := False;
if IpAddr = '' then exit;
try
WSAStartup(2, WSAData);
SockAddrIn.sin_addr.s_addr := inet_addr(PChar(IPAddr));
HostEnt := gethostbyaddr(@SockAddrIn.sin_addr.S_addr, 4, AF_INET);
if HostEnt <> nil then
MacName := StrPas(Hostent^.h_name);
Result := True;
finally
WSACleanup;
end;
end;

{=================================================================
功 能: 返回网络中SQLServer列表
参 数:
List: 需要填充的List
返回值: 成功: True,并填充List 失败 False
备 注:
版 本:
1.0 2002/10/02 22:44:00
=================================================================}
{Function GetSQLServerList(var List: Tstringlist): boolean;
var
i: integer;
SQLServer: Variant;
ServerList: Variant;
begin
Result := False;
List.Clear;
try
SQLServer := CreateOleObject('SQLDMO.Application');
ServerList := SQLServer.ListAvailableSQLServers;
for i := 1 to Serverlist.Count do
list.Add (Serverlist.item(i));
Result := True;
Finally
SQLServer := NULL;
ServerList := NULL;
end;
end;
}
{=================================================================
功 能: 判断Ip协议有没有安装
参 数: 无
返回值: 成功: True 失败: False;
备 注: 该函数还有问题
版 本:
1.0 2002/10/02 21:05:00
=================================================================}
Function IsIPInstalled : boolean;
var
WSData: TWSAData;
ProtoEnt: PProtoEnt;
begin
Result := True;
try
if WSAStartup(2,WSData) = 0 then
begin
ProtoEnt := GetProtoByName('IP');
if ProtoEnt = nil then
Result := False
end;
finally
WSACleanup;
end;
end;


{=================================================================
功 能: 返回网络中的共享资源
参 数:
IpAddr: 机器Ip
List: 需要填充的List
返回值: 成功: True,并填充List 失败: False;
备 注:
WNetOpenEnum function starts an enumeration of network
resources or existing connections.
WNetEnumResource function continues a network-resource
enumeration started by the WNetOpenEnum function.
版 本:
1.0 2002/10/03 07:30:00

=================================================================}
Function GetUserResource(IpAddr: string; var List: TStringList): Boolean;
type
TNetResourceArray = ^TNetResource;//网络类型的数组
Var
i: Integer;
Buf: Pointer;
Temp: TNetResourceArray;
lphEnum: THandle;
NetResource: TNetResource;
Count,BufSize,Res: DWord;
Begin
Result := False;
List.Clear;
if copy(Ipaddr,0,2) <> '//' then
IpAddr := '//'+IpAddr; //填充Ip地址信息
FillChar(NetResource, SizeOf(NetResource), 0);//初始化网络层次信息
NetResource.lpRemoteName := @IpAddr[1];//指定计算机名称
//获取指定计算机的网络资源句柄
Res := WNetOpenEnum( RESOURCE_GLOBALNET, RESOURCETYPE_ANY,
RESOURCEUSAGE_CONNECTABLE, @NetResource,lphEnum);
if Res <> NO_ERROR then exit;//执行失败
while True do//列举指定工作组的网络资源
begin
Count := $FFFFFFFF;//不限资源数目
BufSize := 8192;//缓冲区大小设置为8K
GetMem(Buf, BufSize);//申请内存，用于获取工作组信息
//获取指定计算机的网络资源名称
Res := WNetEnumResource(lphEnum, Count, Pointer(Buf), BufSize);
if Res = ERROR_NO_MORE_ITEMS then break;//资源列举完毕
if (Res <> NO_ERROR) then Exit;//执行失败
Temp := TNetResourceArray(Buf);
for i := 0 to Count - 1 do
begin
//获取指定计算机中的共享资源名称，+2表示删除"//"，
//如//192.168.0.1 => 192.168.0.1
List.Add(Temp^.lpRemoteName + 2);
Inc(Temp);
end;
end;
Res := WNetCloseEnum(lphEnum);//关闭一次列举
if Res <> NO_ERROR then exit;//执行失败
Result := True;
FreeMem(Buf);
End;

{=================================================================
功 能: 返回网络中的工作组
参 数:
List: 需要填充的List
返回值: 成功: True,并填充List 失败: False;
备 注:
版 本:
1.0 2002/10/03 08:00:00
=================================================================}
Function GetGroupList( var List : TStringList ) : Boolean;
type
TNetResourceArray = ^TNetResource;//网络类型的数组
Var
NetResource: TNetResource;
Buf: Pointer;
Count,BufSize,Res: DWORD;
lphEnum: THandle;
p: TNetResourceArray;
i,j: SmallInt;
NetworkTypeList: TList;
Begin
Result := False;
NetworkTypeList := TList.Create;
List.Clear;
//获取整个网络中的文件资源的句柄，lphEnum为返回名柄
Res := WNetOpenEnum( RESOURCE_GLOBALNET, RESOURCETYPE_DISK,
RESOURCEUSAGE_CONTAINER, Nil,lphEnum);
if Res <> NO_ERROR then exit;//Raise Exception(Res);//执行失败
//获取整个网络中的网络类型信息
Count := $FFFFFFFF;//不限资源数目
BufSize := 8192;//缓冲区大小设置为8K
GetMem(Buf, BufSize);//申请内存，用于获取工作组信息
Res := WNetEnumResource(lphEnum, Count, Pointer(Buf), BufSize);
//资源列举完毕 //执行失败
if ( Res = ERROR_NO_MORE_ITEMS ) or (Res <> NO_ERROR ) then Exit;
P := TNetResourceArray(Buf);
for i := 0 to Count - 1 do//记录各个网络类型的信息
begin
NetworkTypeList.Add(p);
Inc(P);
end;
Res := WNetCloseEnum(lphEnum);//关闭一次列举
if Res <> NO_ERROR then exit;
for j := 0 to NetworkTypeList.Count-1 do //列出各个网络类型中的所有工作组名称
begin//列出一个网络类型中的所有工作组名称
NetResource := TNetResource(NetworkTypeList.Items[J]^);//网络类型信息
//获取某个网络类型的文件资源的句柄，NetResource为网络类型信息，lphEnum为返回名柄
Res := WNetOpenEnum(RESOURCE_GLOBALNET, RESOURCETYPE_DISK,
RESOURCEUSAGE_CONTAINER, @NetResource,lphEnum);
if Res <> NO_ERROR then break;//执行失败
while true do//列举一个网络类型的所有工作组的信息
begin
Count := $FFFFFFFF;//不限资源数目
BufSize := 8192;//缓冲区大小设置为8K
GetMem(Buf, BufSize);//申请内存，用于获取工作组信息
//获取一个网络类型的文件资源信息，
Res := WNetEnumResource(lphEnum, Count, Pointer(Buf), BufSize);
//资源列举完毕 //执行失败
if ( Res = ERROR_NO_MORE_ITEMS ) or (Res <> NO_ERROR) then break;
P := TNetResourceArray(Buf);
for i := 0 to Count - 1 do//列举各个工作组的信息
begin
List.Add( StrPAS( P^.lpRemoteName ));//取得一个工作组的名称
Inc(P);
end;
end;
Res := WNetCloseEnum(lphEnum);//关闭一次列举
if Res <> NO_ERROR then break;//执行失败
end;
Result := True;
FreeMem(Buf);
NetworkTypeList.Destroy;
End;

{=================================================================
功 能: 列举工作组中所有的计算机
参 数:
List: 需要填充的List
返回值: 成功: True,并填充List 失败: False;
备 注:
版 本:
1.0 2002/10/03 08:00:00
=================================================================}
Function GetUsers(GroupName: string; var List: TStringList): Boolean;
type
TNetResourceArray = ^TNetResource;//网络类型的数组
Var
i: Integer;
Buf: Pointer;
Temp: TNetResourceArray;
lphEnum: THandle;
NetResource: TNetResource;
Count,BufSize,Res: DWord;
begin
Result := False;
List.Clear;
FillChar(NetResource, SizeOf(NetResource), 0);//初始化网络层次信息
NetResource.lpRemoteName := @GroupName[1];//指定工作组名称
NetResource.dwDisplayType := RESOURCEDISPLAYTYPE_SERVER;//类型为服务器（工作组）
NetResource.dwUsage := RESOURCEUSAGE_CONTAINER;
NetResource.dwScope := RESOURCETYPE_DISK;//列举文件资源信息
//获取指定工作组的网络资源句柄
Res := WNetOpenEnum( RESOURCE_GLOBALNET, RESOURCETYPE_DISK,
RESOURCEUSAGE_CONTAINER, @NetResource,lphEnum);
if Res <> NO_ERROR then Exit; //执行失败
while True do//列举指定工作组的网络资源
begin
Count := $FFFFFFFF;//不限资源数目
BufSize := 8192;//缓冲区大小设置为8K
GetMem(Buf, BufSize);//申请内存，用于获取工作组信息
//获取计算机名称
Res := WNetEnumResource(lphEnum, Count, Pointer(Buf), BufSize);
if Res = ERROR_NO_MORE_ITEMS then break;//资源列举完毕
if (Res <> NO_ERROR) then Exit;//执行失败
Temp := TNetResourceArray(Buf);
for i := 0 to Count - 1 do//列举工作组的计算机名称
begin
//获取工作组的计算机名称，+2表示删除"//"，如//wangfajun=>wangfajun
List.Add(Temp^.lpRemoteName + 2);
inc(Temp);
end;
end;
Res := WNetCloseEnum(lphEnum);//关闭一次列举
if Res <> NO_ERROR then exit;//执行失败
Result := True;
FreeMem(Buf);
end;

{=================================================================
功 能: 列举所有网络类型
参 数:
List: 需要填充的List
返回值: 成功: True,并填充List 失败: False;
备 注:
版 本:
1.0 2002/10/03 08:54:00
=================================================================}
Function GetNetList(var List: Tstringlist): Boolean;
type
TNetResourceArray = ^TNetResource;//网络类型的数组
Var
p: TNetResourceArray;
Buf: Pointer;
i: SmallInt;
lphEnum: THandle;
NetResource: TNetResource;
Count,BufSize,Res: DWORD;
begin
Result := False;
List.Clear;
Res := WNetOpenEnum( RESOURCE_GLOBALNET, RESOURCETYPE_DISK,
RESOURCEUSAGE_CONTAINER, Nil,lphEnum);
if Res <> NO_ERROR then exit;//执行失败
Count := $FFFFFFFF;//不限资源数目
BufSize := 8192;//缓冲区大小设置为8K
GetMem(Buf, BufSize);//申请内存，用于获取工作组信息
Res := WNetEnumResource(lphEnum, Count, Pointer(Buf), BufSize);//获取网络类型信息
//资源列举完毕 //执行失败
if ( Res = ERROR_NO_MORE_ITEMS ) or (Res <> NO_ERROR ) then Exit;
P := TNetResourceArray(Buf);
for i := 0 to Count - 1 do//记录各个网络类型的信息
begin
List.Add(p^.lpRemoteName);
Inc(P);
end;
Res := WNetCloseEnum(lphEnum); //关闭一次列举
if Res <> NO_ERROR then exit; //执行失败
Result := True;
FreeMem(Buf); //释放内存
end;

{=================================================================
功 能: 映射网络驱动器
参 数:
NetPath: 想要映射的网络路径
Password: 访问密码
Localpath 本地路径
返回值: 成功: True 失败: False;
备 注:
版 本:
1.0 2002/10/03 09:24:00
=================================================================}
Function NetAddConnection(NetPath: Pchar; PassWord: Pchar
;LocalPath: Pchar): Boolean;
var
Res: Dword;
begin
Result := False;
Res := WNetAddConnection(NetPath,Password,LocalPath);
if Res <> No_Error then exit;
Result := True;
end;

{=================================================================
功 能: 检测网络状态
参 数:
IpAddr: 被测试网络上主机的IP地址或名称，建议使用Ip
返回值: 成功: True 失败: False;
备 注:
版 本:
1.0 2002/10/03 09:40:00
=================================================================}
Function CheckNet(IpAddr: string): Boolean;
type
PIPOptionInformation = ^TIPOptionInformation;
TIPOptionInformation = packed record
TTL: Byte; // Time To Live (used for traceroute)
TOS: Byte; // Type Of Service (usually 0)
Flags: Byte; // IP header flags (usually 0)
OptionsSize: Byte; // Size of options data (usually 0, max 40)
OptionsData: PChar; // Options data buffer
end;

PIcmpEchoReply = ^TIcmpEchoReply;
TIcmpEchoReply = packed record
Address: DWord; // replying address
Status: DWord; // IP status value (see below)
RTT: DWord; // Round Trip Time in milliseconds
DataSize: Word; // reply data size
Reserved: Word;
Data: Pointer; // pointer to reply data buffer
Options: TIPOptionInformation; // reply options
end;

TIcmpCreateFile = function: THandle; stdcall;
TIcmpCloseHandle = function(IcmpHandle: THandle): Boolean; stdcall;
TIcmpSendEcho = function(
IcmpHandle: THandle;
DestinationAddress: DWord;
RequestData: Pointer;
RequestSize: Word;
RequestOptions: PIPOptionInformation;
ReplyBuffer: Pointer;
ReplySize: DWord;
Timeout: DWord
): DWord; stdcall;

const
Size = 32;
TimeOut = 1000;
var
wsadata: TWSAData;
Address: DWord; // Address of host to contact
HostName, HostIP: String; // Name and dotted IP of host to contact
Phe: PHostEnt; // HostEntry buffer for name lookup
BufferSize, nPkts: Integer;
pReqData, pData: Pointer;
pIPE: PIcmpEchoReply; // ICMP Echo reply buffer
IPOpt: TIPOptionInformation; // IP Options for packet to send
const
IcmpDLL = 'icmp.dll';
var
hICMPlib: HModule;
IcmpCreateFile : TIcmpCreateFile;
IcmpCloseHandle: TIcmpCloseHandle;
IcmpSendEcho: TIcmpSendEcho;
hICMP: THandle; // Handle for the ICMP Calls
begin
// initialise winsock
Result:=True;
if WSAStartup(2,wsadata) <> 0 then begin
Result:=False;
halt;
end;
// register the icmp.dll stuff
hICMPlib := loadlibrary(icmpDLL);
if hICMPlib <> null then begin
@ICMPCreateFile := GetProcAddress(hICMPlib, 'IcmpCreateFile');
@IcmpCloseHandle:= GetProcAddress(hICMPlib, 'IcmpCloseHandle');
@IcmpSendEcho:= GetProcAddress(hICMPlib, 'IcmpSendEcho');
if (@ICMPCreateFile = Nil) or (@IcmpCloseHandle = Nil) or (@IcmpSendEcho = Nil) then begin
Result:=False;
halt;
end;
hICMP := IcmpCreateFile;
if hICMP = INVALID_HANDLE_VALUE then begin
Result:=False;
halt;
end;
end else begin
Result:=False;
halt;
end;
// ------------------------------------------------------------
Address := inet_addr(PChar(IpAddr));
if (Address = INADDR_NONE) then begin
Phe := GetHostByName(PChar(IpAddr));
if Phe = Nil then Result:=False
else begin
Address := longint(plongint(Phe^.h_addr_list^)^);
HostName := Phe^.h_name;
HostIP := StrPas(inet_ntoa(TInAddr(Address)));
end;
end
else begin
Phe := GetHostByAddr(@Address, 4, PF_INET);
if Phe = Nil then Result:=False;
end;

if Address = INADDR_NONE then
begin
Result:=False;
end;
// Get some data buffer space and put something in the packet to send
BufferSize := SizeOf(TICMPEchoReply) + Size;
GetMem(pReqData, Size);
GetMem(pData, Size);
GetMem(pIPE, BufferSize);
FillChar(pReqData^, Size, $AA);
pIPE^.Data := pData;

// Finally Send the packet
FillChar(IPOpt, SizeOf(IPOpt), 0);
IPOpt.TTL := 64;
NPkts := IcmpSendEcho(hICMP, Address, pReqData, Size,
@IPOpt, pIPE, BufferSize, TimeOut);
if NPkts = 0 then Result:=False;

// Free those buffers
FreeMem(pIPE); FreeMem(pData); FreeMem(pReqData);

// --------------------------------------------------------------
IcmpCloseHandle(hICMP);
FreeLibrary(hICMPlib);
// free winsock
if WSACleanup <> 0 then Result:=False;
end;


{=================================================================
功 能: 检测计算机是否上网
参 数: 无
返回值: 成功: True 失败: False;
备 注: uses Wininet
版 本:
1.0 2002/10/07 13:33:00
=================================================================}
function InternetConnected: Boolean;
const
// local system uses a modem to connect to the Internet.
INTERNET_CONNECTION_MODEM = 1;
// local system uses a local area network to connect to the Internet.
INTERNET_CONNECTION_LAN = 2;
// local system uses a proxy server to connect to the Internet.
INTERNET_CONNECTION_PROXY = 4;
// local system's modem is busy with a non-Internet connection.
INTERNET_CONNECTION_MODEM_BUSY = 8;
var
dwConnectionTypes : DWORD;
begin
dwConnectionTypes := INTERNET_CONNECTION_MODEM+ INTERNET_CONNECTION_LAN
+ INTERNET_CONNECTION_PROXY;
Result := InternetGetConnectedState(@dwConnectionTypes, 0);
end;


//关闭网络连接
function NetCloseAll:boolean;
const
NETBUFF_SIZE=$208;
type
NET_API_STATUS=DWORD;
LPByte=PByte;
var
dwNetRet WORD;
i :integer;
dwEntries WORD;
dwTotalEntries WORD;
szClient :LPWSTR;
dwUserName WORD;
Buff :array[0..NETBUFF_SIZE-1]of byte;
Adword :array[0..NETBUFF_SIZE div 4-1] of dword;
NetSessionEnum:function ( ServerName:LPSTR;
ReservedWORD;
Buf:LPByte;
BufLenWORD;
ConnectionCount:LPDWORD;
ConnectionToltalCount:LPDWORD ):NET_API_STATUS;
stdcall;

NetSessionDel:function ( ServerName:LPWSTR;
UncClientName: LPWSTR ;
UserName: dword):NET_API_STATUS;
stdcall;
LibHandle : THandle;
begin
Result:=false;
try
{ 加载 DLL }
LibHandle := LoadLibrary('svrapi.dll');
try
{ 如果加载失败，LibHandle = 0.}
if LibHandle = 0 then
raise Exception.Create('不能加载SVRAPI.DLL');
{ DLL 加载成功，取得到 DLL 输出函数的连接然后调用 }
@NetSessionEnum := GetProcAddress(LibHandle, 'NetSessionEnum');
@NetSessionDel := GetProcAddress(LibHandle, 'NetSessionDel');

if (@NetSessionEnum = nil)or(@NetSessionDel=nil) then
RaiseLastWin32Error { 连接函数失败 }
else
begin
dwNetRet := NetSessionEnum( nil,$32, @Buff,
NETBUFF_SIZE, @dwEntries,
@dwTotalEntries );
if dwNetRet = 0 then
begin
Result := true;
for i:=0 to dwTotalEntries-1 do
begin
Move(Buff,Adword,NETBUFF_SIZE);
szClient:=LPWSTR(Adword[0]);
dwUserName := Adword[2];
dwNetRet := NetSessionDel( nil,szClient,dwUserName);
if( dwNetRet <> 0 ) then
begin
Result := false;
break;
end;
Move(Buff[26],Buff[0],NETBUFF_SIZE-(i+1)*26);
end
end
else
Result := false;
end;
finally
FreeLibrary(LibHandle); // Unload the DLL.
end;
except
end;
end;


end.

ping 127.0.0.1就可以了