XML DA .NET Client Development Toolkit for C# and VB.NET

The XMLDA.NET Client SDK provides a set of .NET classes the handle the communication with XML DA and OPC DA servers. The communication is based on:

• Web services or WCF (Windows Communication Foundation) for XML DA servers
• DCOM for OPC DA servers

The client applications are implemented as XML-DA clients. XML-DA defines only eight methods and is much easier to use than the OPC-DA interface with it's about seventy functions. The state-less nature of the XML DA specification makes XMLDA.NET ideal for ASP/.NET applications.

XMLDA.NET Feature Overview

• Standards based XMLDA.NET
  supports access to OPC-DA and XML-DA servers and has an XML-DA client interface. The use of only standardized interfaces minimizes training requirements and ensures high flexibility.
• Web Services
  XML-DA is designed for web service applications and offers all the features necessary for ASP.NET applications and for access to remote servers. The server communication can either be based on .NET2 web services or .NET WCF.
• Windows Applications
  The XML-DA interface is also well suited for Windows Forms of WPF desktop applications. The low number functions and the state-less design make use simple and straightforward. A Read or Subscribe can be called without first having to create groups etc.
• OPC DA Support
  Access to OPC-DA servers is handled by the XMLDA.NET internal high performance wrapper. Wrapping from XML-DA to OPC-DA is much less problematic than the other direction. The type of the server is not visible to the client. All client applications work with both types of servers.
• Data Binding
  The XMLDA.NET DataBinding subscriptions handle callbacks/server polls and update user classes and Windows Forms/WPF controls without need for user callback handlers. In ASP.NET applications they work together with the ASP.NET DataBind feature.
• Browse Support
  BrowseTree classes handle the server browsing and the display/selection in Windows Forms/WPF TreeView controls.
• ListBuilder
  The ListBuilder tool/class support the interactive definition of the request list need in XML-DA method calls. Coding is reduced to a minimum. Complex applications can be realized with a few lines of code if the ListBuilder and DataBind features are combined.
  
  

XMLDA.NET is provided in version for:

• Web Service communication
  Based on HTTP and simple to configure. HTTPS is the only option for secure communication
• WCF communication
  Has extensive configuration options for various level of security. Only the basicHttp binding is compatible with Web Services
  Is advantageous only if serve and client are WCF based and configured for a communication other than basicHttp.
  

DataBind Subscriptions

XMLDA.NET offers methods beyond the XML DA specification to minimize and simplify the application code. The DataBind subscriptions eliminate the need for the user to handle server callbacks or to poll XML-DA servers. Server items are assigned to different types of application objects:

• Windows Forms or WPF controls
  Server items can be assigned to all kinds of Windows controls such as CheckBoxes, TextBoxes, ListViews. The disply is refreshed whenever the server reports a value change. No user code is required.
• ASP.NET DataBind
  The XMLDA.NET DataBind subscriptions work with the ASP.NET DataBind feature to update displayed item values whenever the browser makes a postback.
• User Classes
  erver items can be assigned to properties of any user defined class. The property SET accessor is executed as the server callback handler.

DataBind subscriptions have optional properties that control how the item value is formatted and how the item quality and errors are handled.

Item List Builder Tool / Class

The ListBuilder tool creates XML files with item definitions as they are required in OPC XML DA server calls. The screen image shows the definition used in the above sample application. The sample application uses the ListBuilder Class to load the XML file and extract the request list for the read call.

Test Client

The TestClient application can access OPC DA and XML DA servers. The type of server accessed depends on the server URL. If it starts with http:// then it's assumed to be the URL of an XML DA server. Otherwise it's assumed to be the ProgID of an OPC DA server.

XMLDA.NET Feature Summary

• XMLDA.NET supports high performance access to multiple OPC-DA and OPC XML-DA servers
• The client application is an OPC XML-DA client, either as an ASP.NET, Windows Forms or WPF application
• ItemListBuilder tool for interactive definition of OPC XML-DA requst lists
• DataBind Subscription automatically refresh displayed item values
• Extra classes are provided for typical tasks like browsing servers or items.
• These methods return the result in Windows defined objects that can easily be displayed.
• The wizards create application projects with a simple client that connects to an OPC server
• Visual Studio 2005 Code Snippets for all server access methods speed-up and simplify coding.
• The Visual Studio integrated help contains detailed information including the OPC specifications.
• Context sensitive help displays the needed information without long searches.
• The OPC XML-DA interface is wrapped directly to the OPC custom interface
• Sample clients are supplied in C# and VB source code
• Developer license with one time fee, no run-time licenses required
• The license includes an Updates/Support subscription for 90 days
  
  

System Requirements

• Windows 7, 8.x, 10 or Windows Server 2008, 2012, 2016
• 32-bit or 64-bit
• NET Framework 4.x
• Visual Studio 2010,2012,2013,2015 or 2017, C# or VB.NET

Download the free Evaluation Version by clicking 'Add To Cart' above. This is a full featured version including the sample client source code. The run time is however limited to 30 minutes, requiring the application to be restarted.