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OpenLNS Programmer's Reference 235
Syntax
dpObject.Read
Element
Description
dpObject
The DataPoint object being acted upon.
Added to API
LNS Release 3. 0.
Write
Summary
Updates the value of the source object controlled by this data
point to match the current value stored in the data point’s
Value, RawValue, and FormattedValue properties.
Writing to either of the Value, RawValue, and
FormattedValue properties updates the values of all three so
that they always match. However, you must call the Write
method to propagate these new values to the source object.
After the Write method is called, OpenLNS will update the
value of the data point’s source object to match the value of
these properties.
For example, if the data point was obtained through a
network variable, the value of the network variable on the
physical device on the network would be updated to match
the values of these properties after the Write method was
called. This ensures that the data point returns a current
value for its source object.
If the AutoWrite property is set to True, this method will
automatically be called every time the RawValue,
FormattedValue, or Value properties are written to.
Note: If you call this method on a DataPoint obtained from a
NetworkVariable or NvMonitorPoint object before reading its
value from the network (either explicitly by calling the Read
method, or implicitly when the AutoRead property is set to
True), or before setting the Data Point’s value with the
RawValue, FormattedValue or Value properties, the DS,
#370 lcaErrLnsDsInvalidArg exception will be thrown.
This indicates that the DataPoint’s buffer is empty.
Availability
Local, full, lightweight, and independent clients. Note that
some objects containing this property are not available to
Independent clients.
Syntax
dpObject.Write
Element
Description
dpObject
The DataPoint object being acted upon.
Added to API
LNS Release 3.20.
Properties
The DataPoint object contains the following properties:
• AutoRead