1.按照上一篇日志“  ”的方法安装动态链接库及相关的注册工作。

2.包含头文件：

　　opcda.h

　　opc_ae.h

　　WTclientAPI.h

3.添加库文件：

　　WTclient.lib (要被加入解决方案)

　　WTclient.dll

4.初始化方法：

　　WTclientCoInit();

　　CoUninitialize();

5.查询所有的OPC server：

1 　　//得到OPC server个数 2     int serverNumber = NumberOfOPCServers(TRUE, ""); 3  4     //得到所有OPC server的名字 5     char buf[100]; 6     CString serverName; 7     for(int i=0; i < serverNumber; i++) 8     { 9         GetOPCServerName (i, buf, 100);10         serverName = buf;11         MessageBox(0, serverName, 0);12     }

6.建立OPC连接：

ConnectionHandle = ConnectOPC ("", serverName, FALSE);

7.断开OPC连接：

DisconnectOPC(ConnectionHandle);

ConnectionHandle = INVALID_HANDLE_VALUE;

8.添加组：

1 CString groupName = "groupName"; 2     DWORD Rate = 100; 3     float DeadBand = 100; 4     HANDLE    hGroup = AddOPCGroup (ConnectionHandle, groupName, &Rate, &DeadBand); 5  6     if (hGroup == INVALID_HANDLE_VALUE) 7     { 8         MessageBox("Error in adding group.", "警告", 0); 9         return;10     }

9.删除组：

void  RemoveOPCGroup (HANDLE hConnect, HANDLE hGroup);

10.添加项目：

CString itemName = "itemName";

HANDLE itemHandle = AddOPCItem(ConnectionHandle, hGroup, itemName);

11.移除项目：

void  RemoveOPCItem (HANDLE hConnect, HANDLE hGroup, HANDLE hItem);

12.读取项目：

//读取项目

VARIANT *pVar = new VARIANT;

FILETIME *pTimeStamp = new FILETIME;

DWORD *pQuality = new DWORD;

ReadOPCItem (ConnectionHandle, hGroup, itemHandle, pVar, pTimeStamp, pQuality);

13.写入项目

VARIANT newVar;

newVar.dblVal = 3.141592;

WriteOPCItem (ConnectionHandle, hGroup, itemHandle, &newVar, 1);

 

我的完整示例：

1 //初始化  2     WTclientCoInit();  3   4     //得到OPC server个数  5     int serverNumber = NumberOfOPCServers(TRUE, "");  6   7     //得到所有OPC server的名字  8     char buf[100];  9     CString serverName; 10     vector
     
       serverNames; 11  12     for(int i=0; i < serverNumber; i++) 13     { 14         GetOPCServerName (i, buf, 100); 15         serverName = buf; 16         serverNames.push_back(serverName); 17     } 18  19     if(serverNumber == 0) 20     { 21         MessageBox("没有可用的OPC服务器", "警告", 0); 22         return ; 23     } 24  25     //建立OPC连接 26     ConnectionHandle = ConnectOPC ("", serverNames[0], TRUE); 27  28     if (ConnectionHandle == INVALID_HANDLE_VALUE) 29     { 30         MessageBox("Error in connecting.", "警告", 0); 31         return; 32     } 33  34     //得到项目个数 35     int itemNum = NumberOfOPCItems(ConnectionHandle); 36  37     //得到所有项目名称 38     char itemBuf[128]; 39     CString iName; 40     vector
      
        itemNames; 41     for(int index = 0; index < itemNum; index++) 42     { 43         if(GetOPCItemName (ConnectionHandle, index, itemBuf, 128)) 44         { 45             iName = itemBuf; 46             itemNames.push_back(iName); 47         } 48         else 49         { 50             MessageBox("读取item名失败", "警告", 0); 51             return ; 52         } 53  54     } 55  56     //得到所有项目属性 57     for(vector
       
        ::iterator iter = itemNames.begin(); iter != itemNames.end(); ++iter) 58     { 59         //得到当前项目的属性个数 60         int propNum = NumberOfItemProperties(ConnectionHandle, *iter); 61  62         for(int i = 0; i < propNum; i++) 63         { 64             //得到属性特征 65             DWORD propertyID = 0; 66             VARTYPE vt; 67             BYTE describtion[1024]; 68             GetItemPropertyDescription (ConnectionHandle, i, &propertyID, &vt, describtion, 1024); 69  70             //读取当前属性值 71             VARIANT value; 72             ReadPropertyValue (ConnectionHandle, *iter, propertyID, &value); 73         } 74     } 75  76     //添加组 77     CString groupName = "groupName"; 78     DWORD Rate = 1; 79     float DeadBand = 1; 80     HANDLE    hGroup = AddOPCGroup (ConnectionHandle, groupName, &Rate, &DeadBand); 81  82     if (hGroup == INVALID_HANDLE_VALUE) 83     { 84         MessageBox("Error in adding group.", "警告", 0); 85         return; 86     } 87  88     //添加项目 89     CString itemName = "Bucket Brigade.Boolean"; 90     HANDLE itemHandle = AddOPCItem(ConnectionHandle, hGroup, itemName); 91  92     if (itemHandle == INVALID_HANDLE_VALUE) 93     { 94         MessageBox("该项不存在.", "警告", 0); 95         return; 96     } 97  98     //得到项目类型 99     VARTYPE type;100     DWORD AccessRights;101     GetOPCItemType(ConnectionHandle, hGroup, "Bucket Brigade.Boolean", &type,  &AccessRights);102 103 104 105     //读取项目106     VARIANT *pVar = new VARIANT;107     FILETIME *pTimeStamp = new FILETIME;108     DWORD *pQuality = new DWORD;109     if( !ReadOPCItem (ConnectionHandle, hGroup, itemHandle, pVar, pTimeStamp, pQuality))110     {111         MessageBox("读取失败.", "警告", 0);112         return ;113     }114 115 116     //写入项目117     VARIANT newVar;118     newVar.vt = 4;119     newVar.fltVal = 3.14;120     if(!WriteOPCItem (ConnectionHandle, hGroup, itemHandle, &newVar, 1))121     {122         MessageBox("写入失败.", "警告", 0);123         return ;124     }125 126 127     //读取项目128     ReadOPCItem (ConnectionHandle, hGroup, itemHandle, pVar, pTimeStamp, pQuality);