WINDOWS 设置DNS自动获取
头文件与库文件#include <Wbemidl.h>#pragma comment(lib,"Wbemuuid.lib")#include <iphlpapi.h>#pragma comment(lib,"iphlpapi.lib")链接#include <comutil.h>#pragma comment(lib, "comsuppw.lib ")#define MALLOC(x) HeapAlloc(GetProcessHeap(), 0, (x)#define FREE(x) HeapFree(GetProcessHeap(), 0, (x)void setDns()HRESULT hr = CoInitializeEx(0, COINIT_MULTITHREADED);hr =CoInitializeSecurity(NULL,-1,NULL,NULL,RPC_C_AUTHN_LEVEL_PKT_PRIVACY,RPC_C_ IMP_LEVEL_IMPERSONATE,NULL,EOAC_SECURE_REFS,NULL);IWbemLocator *pLocator = NULL;IWbemServices *pNamespace = NULL;IWbemClassObject *pClass = NULL;IWbemClassObject *pInputParamClass = NULL;IWbemClassObject *pInputParamInstance = NULL;IWbemClassObject *pOutInst = NULL;char sztm64 = "0"int nNetIndex = 0;/获取默认网卡序号get_default_net_index(nNetIndex);BSTR Path = SysAllocString(L"rootcimv2");BSTR ClassPath = SysAllocString(L"Win32_NetworkAdapterConfiguration");BSTR MethodName1 = SysAllocString(L"SetDNSServerSearchOrder");BSTR MethodName2 = SysAllocString(L"EnableDHCP");LPCWSTR MethodName1ArgName = L"DNSServerSearchOrder"hr = CoCreateInstance(CLSID_WbemLocator, 0, CLSCTX_INPROC_SERVER,IID_IWbemLocator, (void *)&pLocator);hr = pLocator->ConnectServer(Path,NULL, NULL, NULL, 0, NULL, NULL, &pNamespace);hr = CoSetProxyBlanket( pNamespace,RPC_C_AUTHN_WINNT, RPC_C_AUTHZ_NONE, NULL,RPC_C_AUTHN_LEVEL_CALL, RPC_C_IMP_LEVEL_IMPERSONATE, NULL,EOAC_NONE);if(!SUCCEEDED(hr)return ;if(SUCCEEDED(hr)hr = pNamespace->GetObject(ClassPath, 0, NULL, &pClass, NULL); if(!SUCCEEDED(hr)return ;CString cstrSQL ;CString cstrtm;cstrSQL.Format(L"SELECT * FROM Win32_NetworkAdapterConfiguration where InterfaceIndex='%d'",nNetIndex);IEnumWbemClassObject* pEnumerator = NULL;hr = pNamespace->ExecQuery( bstr_t("WQL"), cstrSQL.GetBuffer(), WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY, NULL, &pEnumerator);if (!SUCCEEDED(hr)return ;elseIWbemClassObject *pclsObj;ULONG uReturn = 0;while (pEnumerator) / 推出下一个对象hr = pEnumerator->Next(WBEM_INFINITE, 1, &pclsObj, &uReturn);/没有东西了就跳出去吧if(0 = uReturn)break;VARIANT vtProp;/ WMI 里面网卡的序号hr = pclsObj->Get(L"Index", 0, &vtProp, 0, 0);int n = vtProp.iVal;/.VariantClear(&vtProp);cstrtm.Format(L"Win32_NetworkAdapterConfiguration.Index='%d'",n);BSTR InstancePath = SysAllocString(cstrtm.GetBuffer();if(SUCCEEDED(hr)hr = pClass->GetMethod(MethodName1, 0, &pInputParamClass, NULL); if(!SUCCEEDED(hr)return ; if(SUCCEEDED(hr)hr = pInputParamClass->SpawnInstance(0, &pInputParamInstance); if(!SUCCEEDED(hr)return ; if(SUCCEEDED(hr)hr = pInputParamInstance->Put(MethodName1ArgName, 0, NULL, 0); if(!SUCCEEDED(hr)return ; if(SUCCEEDED(hr)hr = pNamespace->ExecMethod(InstancePath, MethodName1, 0, NULL, pInputParamInstance, &pOutInst, NULL);if(!SUCCEEDED(hr)return; if(SUCCEEDED(hr)hr = pNamespace->ExecMethod(InstancePath, MethodName2, 0, NULL, NULL, &pOutInst, NULL);if(!SUCCEEDED(hr)return ;SysFreeString(InstancePath);SysFreeString(Path);SysFreeString(ClassPath);SysFreeString(MethodName1);SysFreeString(MethodName2);if(pOutInst)pOutInst->Release();if(pInputParamInstance) pInputParamInstance->Release();if(pInputParamClass) pInputParamClass->Release();if(pClass) pClass->Release();if(pNamespace) pNamespace->Release();if(pLocator) pLocator->Release();CoUninitialize();return ;PMIB_IPFORWARDTABLE MyGetIpForwardTable(BOOL bOrder) PMIB_IPFORWARDTABLE pIpRouteTab = NULL;DWORD dwActualSize = 0;/ 查询所需缓冲区的大小if(:GetIpForwardTable(pIpRouteTab, &dwActualSize, bOrder) = ERROR_INSUFFICIENT_BUFFER)/ 为 MIB_IPFORWARDTABLE 结构申请内存pIpRouteTab = (PMIB_IPFORWARDTABLE):GlobalAlloc(GPTR, dwActualSize); / 获取路由表if(:GetIpForwardTable(pIpRouteTab, &dwActualSize, bOrder) = NO_ERROR) return pIpRouteTab;:GlobalFree(pIpRouteTab);return NULL; void get_default_net_index(int& nIndex)PMIB_IPFORWARDTABLE pIpRouteTable = MyGetIpForwardTable(TRUE); if(pIpRouteTable != NULL)DWORD i, dwCurrIndex;struct in_addr inadDest;struct in_addr inadMask;struct in_addr inadGateway;PMIB_IPADDRTABLE pIpAddrTable = NULL;for (i = 0; i < pIpRouteTable->dwNumEntries; i+)dwCurrIndex = pIpRouteTable->tablei.dwForwardIfIndex;/ 目的地址inadDest.s_addr = pIpRouteTable->tablei.dwForwardDest;if (0 = inadDest.s_addr)/ 子网掩码 inadMask.s_addr = pIpRouteTable->tablei.dwForwardMask;/ 网关地址 inadGateway.s_addr = pIpRouteTable->tablei.dwForwardNextHop;nIndex = pIpRouteTable->tablei.dwForwardIfIndex;break;FREE(pIpRouteTable);
