node-opcua基础连接读写普通变量

JS菜鸟整理。

下载：

GitHub - node-opcua/node-opcua-sample: a simple OPCUA sample client to demonstrate how to use node-opcua SDKhttps://github.com/node-opcua/node-opcua-sample正常：

npm install

修改simple_client.js:

var opcua = require('node-opcua');
var nodeId = require("node-opcua-nodeid");
var async = require("async");
var DataType = opcua.DataType;
var AttributeIds = opcua.AttributeIds;



var connectionOption = {};

connectionOption.securityPolicy = opcua.SecurityPolicy.None;
connectionOption.securityMode = opcua.MessageSecurityMode.None;
connectionOption.keepSessionAlive = true;

client = opcua.OPCUAClient.create(connectionOption);

async function connect_opcua_client() {
  try{
    await client.connect("opc.tcp://192.168.3.1:4840");
  } catch (err) {
    console.log(err);
    return;
  }
    if (!client) {
      console.log("Client not yet created & connected, cannot getEndpoints!");
      return;
    }
  // verbose_log("Create session ...");
  try {
        if (!client) {
          return;
        }
        var userIdentity = {};
        if (0) {
          userIdentity.userName = "XXXX";
          userIdentity.password = "XXX.";
          userIdentity.type = opcua.UserTokenType.UserName; // New TypeScript API parameter
        }
        else {
          userIdentity.type = opcua.UserTokenType.Anonymous;
        }


        session = await client.createSession(userIdentity);
        if (!session) {
          console.log("Create session failed!");
          return;
        }
        console.log("Create session sucees!");
    } catch (err) {
    console.log(err);
    return;
  }

  //read value:
  var nodeIdS = "ns=1;s=XXXX";
  try
  {
    const dataValue = await session.read({ nodeId:nodeIdS, attributeId: AttributeIds.Value });

      if (dataValue.statusCode !== opcua.StatusCodes.Good) {
            console.log("Could not read ", nodeIdS);
        }
    else
    {
        console.log(" read value success = ", dataValue.toString());
    }
  } catch(err)
  {
    console.log(err);
    return;
  }





    // var _toDataType = function (type) {
    //     if (type === 'Boolean') {
    //         return opcua.DataType.Boolean;
    //     } else if (type === 'SByte') {
    //         return opcua.DataType.SByte;
    //     } else if (type === 'Byte') {
    //         return opcua.DataType.Byte;
    //     } else if (type === 'Int16') {
    //         return opcua.DataType.Int16;
    //     } else if (type === 'UInt16') {
    //         return opcua.DataType.UInt16;
    //     } else if (type === 'Int32') {
    //         return opcua.DataType.Int32;
    //     } else if (type === 'UInt32') {
    //         return opcua.DataType.UInt32;
    //     } else if (type === 'Int64') {
    //         return opcua.DataType.Int64;
    //     } else if (type === 'UInt64') {
    //         return opcua.DataType.UInt64;
    //     } else if (type === 'Float') {
    //         return opcua.DataType.Float;
    //     } else if (type === 'Double') {
    //         return opcua.DataType.Double;
    //     } else if (type === 'String') {
    //         return opcua.DataType.String;
    //     } else if (type === 'DateTime') {
    //         return opcua.DataType.DateTime;
    //     } else if (type === 'Guid') {
    //         return opcua.DataType.Guid;
    //     } else if (type === 'ByteString') {
    //         return opcua.DataType.ByteString;
    //     }
    // }



  //write value:
  try
  {
    var nodesToWrite = [
    {
        nodeId: nodeIdS,
        attributeId: opcua.AttributeIds.Value,
        value: /*new DataValue(*/{
            value: {/* Variant */
                dataType: opcua.DataType.Double,
                value: 2.2
            }
        }
    }];


    session.write(nodesToWrite, function (err, statusCodes) {
                if (err) {
                    console.log(' setValue error: ' + err);
                }
            });

    } catch(err)
      {
        console.log(err);
        return;
      }
    console.log(' setValue susccess: !');
}

connect_opcua_client();

标签：node,return,log,DataType,读写,else,type,opcua
来源： https://blog.csdn.net/qq_37887537/article/details/120314710