Shared Variable code

The message pipeline model for Microsoft Dynamics 365 defines a parameter collection of custom data values in the execution context that is passed through the pipeline and shared among registered plug-ins, even from different 3rd party developers. This collection of data can be used by different plug-ins to communicate information between plug-ins and enable chain processing where data processed by one plug-in can be processed by the next plug-in in the sequence and so on. This feature is especially useful in pricing engine scenarios where multiple pricing plug-ins pass data between one another to calculate the total price for a sales order or invoice. Another potential use for this feature is to communicate information between a plug-in registered for a pre-event and a plug-in registered for a post-event.

The name of the parameter that is used for passing information between plug-ins is SharedVariables. This is

 a collection of key\value pairs. At run time, plug-ins can add, read, or modify properties in the SharedVariables

 collection. This provides a method of information communication among plug-ins

 public class PreEventPlugin : IPlugin
    {
        public void Execute(IServiceProvider serviceProvider)
        {
            // Obtain the execution context from the service provider.
            Microsoft.Xrm.Sdk.IPluginExecutionContext context = (Microsoft.Xrm.Sdk.IPluginExecutionContext)
                serviceProvider.GetService(typeof(Microsoft.Xrm.Sdk.IPluginExecutionContext));

            // Create or retrieve some data that will be needed by the post event
            // plug-in. You could run a query, create an entity, or perform a calculation.
            //In this sample, the data to be passed to the post plug-in is
            // represented by a GUID.
            Guid contact = new Guid("{74882D5C-381A-4863-A5B9-B8604615C2D0}");

            // Pass the data to the post event plug-in in an execution context shared
            // variable named PrimaryContact.
            context.SharedVariables.Add("PrimaryContact", (Object)contact.ToString());
        }
    }

    public class PostEventPlugin : IPlugin
    {
        public void Execute(IServiceProvider serviceProvider)
        {
            // Obtain the execution context from the service provider.
            Microsoft.Xrm.Sdk.IPluginExecutionContext context = (Microsoft.Xrm.Sdk.IPluginExecutionContext)
                serviceProvider.GetService(typeof(Microsoft.Xrm.Sdk.IPluginExecutionContext));

            // Obtain the contact from the execution context shared variables.
            if (context.SharedVariables.Contains("PrimaryContact"))
            {
                Guid contact =
                    new Guid((string)context.SharedVariables["PrimaryContact"]);

                // Do something with the contact.
            }
        }
    }