图：Ping通的情况
图：Ping失败的情况
下面是源代码(VB6)：(完善的出错控制，所以是个好函数）
Option Explicit
Private Const IP_SUCCESS As Long = 0
Private Const IP_STATUS_BASE As Long = 11000
Private Const IP_BUF_TOO_SMALL As Long = (11000 + 1)
Private Const IP_DEST_NET_UNREACHABLE As Long = (11000 + 2)
Private Const IP_DEST_HOST_UNREACHABLE As Long = (11000 + 3)
Private Const IP_DEST_PROT_UNREACHABLE As Long = (11000 + 4)
Private Const IP_DEST_PORT_UNREACHABLE As Long = (11000 + 5)
Private Const IP_NO_RESOURCES As Long = (11000 + 6)
Private Const IP_BAD_OPTION As Long = (11000 + 7)
Private Const IP_HW_ERROR As Long = (11000 + 8)
Private Const IP_PACKET_TOO_BIG As Long = (11000 + 9)
Private Const IP_REQ_TIMED_OUT As Long = (11000 + 10)
Private Const IP_BAD_REQ As Long = (11000 + 11)
Private Const IP_BAD_ROUTE As Long = (11000 + 12)
Private Const IP_TTL_EXPIRED_TRANSIT As Long = (11000 + 13)
Private Const IP_TTL_EXPIRED_REASSEM As Long = (11000 + 14)
Private Const IP_PARAM_PROBLEM As Long = (11000 + 15)
Private Const IP_SOURCE_QUENCH As Long = (11000 + 16)
Private Const IP_OPTION_TOO_BIG As Long = (11000 + 17)
Private Const IP_BAD_DESTINATION As Long = (11000 + 18)
Private Const IP_ADDR_DELETED As Long = (11000 + 19)
Private Const IP_SPEC_MTU_CHANGE As Long = (11000 + 20)
Private Const IP_MTU_CHANGE As Long = (11000 + 21)
Private Const IP_UNLOAD As Long = (11000 + 22)
Private Const IP_ADDR_ADDED As Long = (11000 + 23)
Private Const IP_GENERAL_FAILURE As Long = (11000 + 50)
Private Const MAX_IP_STATUS As Long = (11000 + 50)
Private Const IP_PENDING As Long = (11000 + 255)
Private Const PING_TIMEOUT As Long = 500
Private Const WS_VERSION_REQD As Long = &H101
Private Const MIN_SOCKETS_REQD As Long = 1
Private Const SOCKET_ERROR As Long = -1
Private Const INADDR_NONE As Long = &HFFFFFFFF
Private Const MAX_WSADescription As Long = 256
Private Const MAX_WSASYSStatus As Long = 128
Private Type ICMP_OPTIONS
Ttl As Byte
Tos As Byte
Flags As Byte
OptionsSize As Byte
OptionsData As Long
End Type
Private Type ICMP_ECHO_REPLY
Address As Long
status As Long
RoundTripTime As Long
DataSize As Long
DataPointer As Long
Options As ICMP_OPTIONS
Data As String * 250
End Type
Private Type WSADATA
wVersion As Integer
wHighVersion As Integer
szDescription(0 To MAX_WSADescription) As Byte
szSystemStatus(0 To MAX_WSASYSStatus) As Byte
wMaxSockets As Long
wMaxUDPDG As Long
dwVendorInfo As Long
End Type
Private Declare Function IcmpCreateFile Lib "icmp.dll" () As Long
Private Declare Function IcmpCloseHandle Lib "icmp.dll" (ByVal IcmpHandle As Long) As Long
Private Declare Function IcmpSendEcho Lib "icmp.dll" (ByVal IcmpHandle As Long, ByVal DestinationAddress As Long, ByVal RequestData As String, ByVal RequestSize As Long, ByVal RequestOptions As Long, ReplyBuffer As ICMP_ECHO_REPLY, ByVal ReplySize As Long, ByVal Timeout As Long) As Long
Private Declare Function WSAGetLastError Lib "wsock32" () As Long
Private Declare Function WSAStartup Lib "wsock32" (ByVal wVersionRequired As Long, lpWSADATA As WSADATA) As Long
Private Declare Function WSACleanup Lib "wsock32" () As Long
Private Declare Function gethostname Lib "wsock32" (ByVal szHost As String, ByVal dwHostLen As Long) As Long
Private Declare Function gethostbyname Lib "wsock32" (ByVal szHost As String) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (xDest As Any, xSource As Any, ByVal nbytes As Long)
Private Declare Function inet_addr Lib "wsock32" (ByVal s As String) As Long
Private Function GetStatusCode(status As Long) As String
On Error GoTo Z
Dim Msg As String
Select Case status
Case IP_SUCCESS: Msg = "ip success"
Case INADDR_NONE: Msg = "inet_addr: bad IP format"
Case IP_BUF_TOO_SMALL: Msg = "ip buf too_small"
Case IP_DEST_NET_UNREACHABLE: Msg = "ip dest net unreachable"
Case IP_DEST_HOST_UNREACHABLE: Msg = "ip dest host unreachable"
Case IP_DEST_PROT_UNREACHABLE: Msg = "ip dest prot unreachable"
Case IP_DEST_PORT_UNREACHABLE: Msg = "ip dest port unreachable"
Case IP_NO_RESOURCES: Msg = "ip no resources"
Case IP_BAD_OPTION: Msg = "ip bad option"
Case IP_HW_ERROR: Msg = "ip hw_error"
Case IP_PACKET_TOO_BIG: Msg = "ip packet too_big"
Case IP_REQ_TIMED_OUT: Msg = "ip req timed out"
Case IP_BAD_REQ: Msg = "ip bad req"
Case IP_BAD_ROUTE: Msg = "ip bad route"
Case IP_TTL_EXPIRED_TRANSIT: Msg = "ip ttl expired transit"
Case IP_TTL_EXPIRED_REASSEM: Msg = "ip ttl expired reassem"
Case IP_PARAM_PROBLEM: Msg = "ip param_problem"
Case IP_SOURCE_QUENCH: Msg = "ip source quench"
Case IP_OPTION_TOO_BIG: Msg = "ip option too_big"
Case IP_BAD_DESTINATION: Msg = "ip bad destination"
Case IP_ADDR_DELETED: Msg = "ip addr deleted"
Case IP_SPEC_MTU_CHANGE: Msg = "ip spec mtu change"
Case IP_MTU_CHANGE: Msg = "ip mtu_change"
Case IP_UNLOAD: Msg = "ip unload"
Case IP_ADDR_ADDED: Msg = "ip addr added"
Case IP_GENERAL_FAILURE: Msg = "ip general failure"
Case IP_PENDING: Msg = "ip pending"
Case PING_TIMEOUT: Msg = "ping timeout"
Case Else: Msg = "unknown msg returned"
End Select
GetStatusCode = Msg
Exit Function
Z:
GetStatusCode = ""
End Function
Private Function Ping(sAddress As String, sDataToSend As String, ECHO As ICMP_ECHO_REPLY) As Long
On Error GoTo Z
Dim hPort As Long
Dim dwAddress As Long
dwAddress = inet_addr(sAddress)
If dwAddress <> INADDR_NONE Then
hPort = IcmpCreateFile()
If hPort Then
Call IcmpSendEcho(hPort, dwAddress, sDataToSend, Len(sDataToSend), 0, ECHO, Len(ECHO), PING_TIMEOUT)
Ping = ECHO.status
Call IcmpCloseHandle(hPort)
End If
Else
Ping = INADDR_NONE
End If
Exit Function
Z:
Ping = INADDR_NONE
End Function
'（Ping函数）
' 参数：目标IP地址
'返回值：存在返回True，否则返回False
Public Function PingIp(ByVal szIp As String) As Boolean
On Error GoTo Z
Dim WSAD As WSADATA
Dim ECHO As ICMP_ECHO_REPLY
Dim ret As Long
If WSAStartup(WS_VERSION_REQD, WSAD) = IP_SUCCESS Then
ret = Ping(Trim(szIp), "tanaya", ECHO)
If InStr(1, GetStatusCode(ret), "success") <> 0 Then
WSACleanup
PingIp = True
Exit Function
End If
End If
PingIp = False
Exit Function
Z:
PingIp = False
End Function