Please ensure Javascript is enabled for purposes of website accessibility
Powered by Zoomin Software. For more details please contactZoomin

AF SDK Reference

AFValue.SetAnnotation Method

  • Last UpdatedJan 12, 2026
  • 4 minute read
AFValue.SetAnnotation Method
Associates an annotation with this AF value.

Namespace:  OSIsoft.AF.Asset
Assembly:  OSIsoft.AFSDK (in OSIsoft.AFSDK.dll) Version: 3.2.0.7

Syntax

public void SetAnnotation(
	Object annotation
)
Public Sub SetAnnotation ( 
	annotation As Object
)

Dim instance As AFValue
Dim annotation As Object

instance.SetAnnotation(annotation)
public:
void SetAnnotation(
	Object^ annotation
)
member SetAnnotation : 
        annotation : Object -> unit 

Parameters

annotation
Type: SystemObject
The value of the annotation to associate with this AF value. It can be a list of structured AFAnnotations or a single value of type Object. To remove an annotation from an existing value, set the annotation value to an Empty string.

Exceptions

ExceptionCondition
ArgumentNullException The annotation is .
NotSupportedException The data reference does not support the this method, or a data reference has not been configured.

Remarks

This method will associate the annotation with this AF value; however, the annotation is not committed until the value is updated using UpdateValue(AFValue, AFUpdateOption)

The attribute must indicate that it supports setting annotations by including the Annotations flag in its SupportedDataMethods.

Note Notes to Callers
This method, property, or class is not available in the legacy .NET 3.5 version of the SDK.

Security note Security Note
You must have WriteData security rights to write a data value.

Examples

// This example demonstrates how to create an attribute for an
// element and retrieve and set annotations on values.

// Get the Database
PISystems myPISystems = new PISystems();
PISystem myPISystem = myPISystems.DefaultPISystem;
AFDatabase myDB = myPISystem.Databases.DefaultDatabase;

// Create an Element
AFElement myElement = myDB.Elements.Add("MyElement");

// Create an Attribute
AFAttribute myAttribute = myElement.Attributes.Add("MyAttribute");
myAttribute.DefaultUOM = myPISystem.UOMDatabase.UOMs["kelvin"];
myAttribute.DataReferencePlugIn = AFDataReference.GetPIPointDataReference(myPISystem);
myAttribute.ConfigString = @"\\%Server%\sinusoid;ReadOnly=False";

// Create New Simple Annotation
AFValue myValue1 = new AFValue(155.432, AFTime.Now);
myValue1.SetAnnotation("New Event with Simple Annotation");
myAttribute.Data.UpdateValue(myValue1, AFUpdateOption.InsertNoCompression);

// Update an Existing Annotation
myValue1.SetAnnotation(100);
myAttribute.Data.UpdateValue(myValue1, AFUpdateOption.Replace);

// Create an AFFile to be used as an Annotation value
string path = System.IO.Path.Combine(System.IO.Path.GetTempPath(), "TestFile.txt");
using (System.IO.File.Create(path)) { }
AFFile myFile = new AFFile();
myFile.Upload(path);

// Create New Structured Annotation
AFAnnotations myAnnotations = new AFAnnotations();
AFValue myValue2 = new AFValue(255.543);
AFAnnotation myAnnotation = myAnnotations.Add("Annotation#1", 400.456);
myAnnotation.Description = "1st Annotation is a Double.";
myAnnotation = myAnnotations.Add("Annotation#2", "My Annotation Value");
myAnnotation.Description = "2nd Annotation is a String.";
myAnnotation = myAnnotations.Add("Annotation#3", myFile);
myAnnotation.Description = "3rd Annotation is an AFFile.";
myValue2.SetAnnotation(myAnnotations);
myAttribute.Data.UpdateValue(myValue2, AFUpdateOption.InsertNoCompression);

// Read Annotations
object theAnnotation = myValue1.GetAnnotation();
DisplayAnnotation(myValue1, theAnnotation);

theAnnotation = myValue2.GetAnnotation();
DisplayAnnotation(myValue2, theAnnotation);

AFValue myValue = myAttribute.GetValue();
theAnnotation = myValue.GetAnnotation();
DisplayAnnotation(myValue, theAnnotation);
/// <summary>
/// Display information about the annotated value.
/// </summary>
/// <param name="theValue">
/// The AFValue associated with the specified annotation value.
/// </param>
/// <param name="theAnnotation">
/// The annotation value associated with the specified AFValue.
/// </param>
static private void DisplayAnnotation(AFValue theValue, object theAnnotation)
{
    AFAnnotations theAnnotations = theAnnotation as AFAnnotations;
    if (theAnnotations == null)
    {
        Console.WriteLine("Simple Annotation for Value '{0}' = '{1}'", theValue, theAnnotation);
    }
    else
    {
        Console.WriteLine("Structured Annotation for Value '{0}':", theValue);
        foreach (AFAnnotation item in theAnnotations)
        {
            Console.WriteLine("  Value = '{0}', Description = '{1}', Creator = '{2}'",
                item.Value, item.Description, item.Creator);
        }
    }
}

Version Information

AFSDK


See Also

In This Topic
Related Links
TitleResults for “How to create a CRG?”Also Available in