ReadItem Method (IEasyDAClientExtension2)

Reads a typed named item from an OPC server. A typed value, quality and timestamp are returned.

The server can be local or can be remotely accessed via DCOM. Optionally, an access path can be specified or a specific data type can be requested.

The ReadItem method only waits for the first update from the server (or until the timeout elapses); it does not wait until the quality becomes "uncertain" or "good".

Overload List

Overload	Description
ReadItem<TValue>(IEasyDAClient,ServerDescriptor,DANodeDescriptor)	Reads a typed named item from an OPC server. A typed value, quality and timestamp are returned. Reads a typed named item using descriptor objects for the OPC server and OPC-DA item.
ReadItem<TValue>(IEasyDAClient,ServerDescriptor,DANodeDescriptor,DAReadParameters)	Reads a typed named item from an OPC server. A typed value, quality and timestamp are returned. Reads a typed named item using descriptor objects for the OPC server and OPC-DA item, and specifying read parameters such as the data source or value age.
ReadItem<TValue>(IEasyDAClient,String,String,String)	Reads a typed named item from an OPC server. A typed value, quality and timestamp are returned. Reads a typed named item using individual parameters specifying its location, and a specific data type.
ReadItem<TValue>(IEasyDAClient,String,String,String,Int32)	Reads a typed named item from an OPC server. A typed value, quality and timestamp are returned. Reads a typed named item using individual parameters specifying its location, and value age.

Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2012, Windows Server 2016; .NET Core, .NET 5, .NET 6: Linux, macOS, Microsoft Windows

Reference

IEasyDAClientExtension2 Class
IEasyDAClientExtension2 Members