ExternalMethodAttribute Class

Assembly: CodeEffects.Rule.Common.dll
Namespace: CodeEffects.Rule.Common.Attributes

Summary

IMPORTANT Generic methods with generic params cannot be used in Source XML as in-rule methods or rule actions. Use plain .Net class(es) if your source object declares generic methods.

When applied to a source object, this attribute references an external qualified public method to be used as an in-rule method. To qualify, the method must be public, static or instance, return a value type and must either be parameterless or declare only parameters of the source object type or of any value type supported by Code Effects.

Syntax

[AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, AllowMultiple = true, Inherited = true)]
public class ExternalMethodAttribute : System.Attribute,
	CodeEffects.Rule.Common.Attributes.IExternalAttribute,
	CodeEffects.Rule.Common.Attributes.ISortable

Properties

Remarks

This attribute is optional and is used to reference external methods that you want to use as in-rule methods. An exception is thrown if the attribute references a non-qualified method. If the external method defines multiple overloads, decorate each overload that you intend to use as an in-rule method with the [MethodAttribute](/decision-automation/rule-common-attributes-method), and assign a unique display name to each using its DisplayName property.

Remember that external static or instance in-rule methods can accept your source object as a parameter. When a rule author uses such a method in a rule, parameters of the source object type are not displayed — Rule Editor passes them automatically. In the Rule XML, the parameter of the source object type is represented as this.

Example

using System;
using CodeEffects.Rule.Common.Attributes;

namespace TestLibrary
{
	[ExternalMethod(typeof(Helper), nameof(Helper.GetUtc))]
	public class Test
	{
		// Class implementation
	}

	public class Helper
	{
		[Method("Get UTC Date", "Gets a new UTC value")]
		public static DateTime GetUtc()
		{
			return DateTime.UtcNow;
		}
	}
}