gOPCClassicConnector.gAsyncWriteItems Method

Top  Previous  Next

Description

Used to write values to OPC Items asynchronously.

This method does not freeze your application like a synchronous method.

And because this is an asynchronous method, results comes with an event: gAsyncWriteItemsCompleted

 

VB syntax

gOPCClassicConnector.gAsyncWriteItems(itemsToWrite() As gOPCClassicReadWriteObject, transactionID As String)

 

C# syntax

gOPCClassicConnector.gAsyncWriteItems(gOPCClassicReadWriteObject[] ItemsToWrite, string transactionID)

 

Parameters

itemsToWrite

Array of ItemIDs of OPC Items that you want to write to.

 

transactionID

Transaction id is ID of asynchronous operation, a unique string.

Used in gAsyncWriteItemsCompleted  event or to cancel asynchronous operation.

 

Return Type

gOPCClassicFunctionResult

 

C# code example

  try

            {

                //Step1: Create an array of read-write object , assign ItemIDs and assign values you want to write

                GelecekCommon.gOPCClassicReadWriteObject[] read_write_objs = new GelecekCommon.gOPCClassicReadWriteObject[2];

 

                for (int i = 0; i < read_write_objs.Length; i++)

                {

                    read_write_objs[i] = new GelecekCommon.gOPCClassicReadWriteObject();

                }

                read_write_objs[0].ItemID = txtItemID1.Text;

                read_write_objs[0].Value = txtValue1.Text; //Be careful, Text should be able to convert to data type of OPC Item

 

                read_write_objs[1].ItemID = txtItemID2.Text;

                read_write_objs[1].Value = txtValue2.Text; //Be careful, Text should be able to convert to data type of OPC Item

 

                //Step2: Run gAsyncWriteItems method  

                GelecekCommon.gOPCClassicFunctionResult function_result = gOPCClassicConnector1.gAsyncWriteItems(read_write_objs, txtTransactionID.Text);

 

                //Step3: Check function result to be sure about a successfull writing

                //For a successfull write, function result should be "OK" 

                txtFunctionResult.Text = function_result.ToString();

 

            }

            catch (Exception ex)

            {

                MessageBox.Show(ex.Message);

            }