QuickOPC User's Guide and Reference
ReadItem Method (IEasyDAClientExtension)



OpcLabs.EasyOpcClassic Assembly > OpcLabs.EasyOpc.DataAccess Namespace > IEasyDAClientExtension Class : ReadItem Method
Reads a named item from an OPC server. 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
OverloadDescription
Reads a named item from an OPC server. Value, quality and timestamp are returned. Reads a named item using an item arguments objects, and read parameters.  
Reads a named item from an OPC server. Value, quality and timestamp are returned. Reads a named item using an object that holds all necessary arguments.  
Reads a named item from an OPC server. Value, quality and timestamp are returned. Reads a named item using descriptor objects for the OPC server and OPC-DA item.  
Reads a named item from an OPC server. Value, quality and timestamp are returned. Reads a 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.  
Reads a named item from an OPC server. Value, quality and timestamp are returned. Reads a named item using individual parameters specifying its location, and a specific data type.  
Reads a named item from an OPC server. Value, quality and timestamp are returned. Reads a named item using individual parameters specifying its location, a specific data type, and value age.  
Reads a named item from an OPC server. Value, quality and timestamp are returned. Reads a named item using individual parameters specifying its location, and using server's canonical data type.  
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

See Also

Reference

IEasyDAClientExtension Class
IEasyDAClientExtension Members