It allows writing the defined block in the data group (defined on the "Data
" tab) to the OPC server.
Boolean Write(Long Attr, Long From, Long To)
|Attr||(Long) the way of the transfer: (see OPC DA Basic terms)|
0 - asynchronous access (recommended)
2 - synchronous access
|From||(Long) Index of the first value (zero-based index).|
|To||(Long) Index of the last value (zero-based index). -1 = to the end.|
true - on success
false - on error
Writing to the OPC server proceeds always into DEVICE
and yet it is recommended to use the Attr
value 0, i.e. the asynchronous access. When writing to DEVICE
it is necessary to communicate with the device making the Write
method take longer time in synchronous access slowing down the whole appication.
The Write method needn't be called if the "Auto send to server when writing to item" configurator is checked (on the "Parameters" tab) because the data are then "written" automatically.
Writing all values to the OPC server:
var oOpcGroup = pMe.Pm("/OpcClient/Group1");
if (oOpcGroup.Write(0, 0, -1))
//... on success
//... on error