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Summary

This example demonstrates how to parse Tags using three distinct methods.

Technical Information

There are various methods to address challenges when parsing Tags. This example showcases three approaches: simple script-based parsing, expression-driven tag changes, and event-driven parsing. Depending on the complexity of the task and required flexibility, these methods can be employed as solutions.

Method 1: Parsing Tags via Client Script

In this method, the button in the purple box is linked to a script called ParseTags_Client. When pressed, it invokes the ParseTags_Client method, which calls the asynchronous Main method, passing the name of the tag obtained from @Tag.TagTestClient.GetName() as a parameter. The Main method updates MessageClassClient with the text "TagName: " followed by the actual tag name, which is displayed in a message box. It also traces the tag name for logging purposes. The aforementioned code is seen below:

public async Task ParseTags_Client(object sender, System.Windows.Input.InputEventArgs e) {
    @Script.Class.ParseTags_Client.Main(@Tag.TagTestClient.GetName());
    // Sends the desired tag to the function, receives a response string TagName: <tag name>
}

Method 2: Using Expressions and ScriptClass

In this method, the button in the blue box triggers a tag's value to change, this tag is configured as a trigger to the expression Script.Class.ParseTags.ParseTagServer(Tag.TagTestServer.GetName()). This expression calls the ParseTagServer method from the ParseTags script, passing the name of the tag obtained from Tag.TagTestServer.GetName() as a parameter. The ParseTagServer method traces the tag name for logging purposes and updates the MessageExpressions with "TagName: " followed by the actual tag name, which is displayed in a message box when triggered.

Method 3: Complex Parsing with Event Handling

The third example demonstrates a more complex setup. Upon solution initialization, the Initialize method from the ParseTags ScriptClass is called. This method initializes a list and feeds two Tags into it. When the values of these tags change, an event is triggered, displaying the updated tag value in a message box. The ObjectReferenceHandler method logs the tag’s name and value when the event is triggered. To illustrate this, a button was included. When pressed, it changes the tagTestServer's value, causing this event to be registered and the new value to be displayed in the message box.  

Reference Information

→ See Unified Namespaces Enumerations for more information.

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