Developing a Custom Referenced Functoid

Custom referenced functoids do not copy implementation code inline into the map. Instead, a reference to the assembly, class, and method is placed in the extension object file associated with the generated style sheet and called at run time.

Example

The following example illustrates how to create a custom referenced functoid for concatenating two strings. It relies on a resource file containing three string resources and a 16x16-pixel bitmap resource.

using System;  
using Microsoft.BizTalk.BaseFunctoids;  
using System.Reflection;  
  
namespace Microsoft.Samples.BizTalk.CustomFunctoid  
{  
    /// <summary>  
    /// Performs a string concatenation through assembly referenced function. Assembly must be deployed with the BizTalk solution.  
    /// </summary>  
    public class CustomStringConcatFunctoid : BaseFunctoid  
    {  
        public CustomStringConcatFunctoid()  
            : base()  
        {  
            //ID for this functoid  
            this.ID = 6001;  
  
            // Resource assembly must be ProjectName.ResourceName if building with VS.Net  
            SetupResourceAssembly("Microsoft.Samples.BizTalk.CustomFunctoid.CustomFunctoidResources", Assembly.GetExecutingAssembly());  
  
            // Pass the resource ID names for functoid name, tooltip  
            // description and the 16x16 bitmap for the Map palette  
            SetName("IDS_CUSTOMSTRINGCONCATFUNCTOID_NAME");  
            SetTooltip("IDS_CUSTOMSTRINGCONCATFUNCTOID_TOOLTIP");  
            SetDescription("IDS_CUSTOMSTRINGCONCATFUNCTOID_DESCRIPTION");  
            SetBitmap("IDB_CUSTOMSTRINGCONCATFUNCTOID_BITMAP");  
  
            // Put this string handling function under the String   
            // Functoid tab in the Visual Studio toolbox for functoids  
            this.Category = FunctoidCategory.String;  
  
            // 2 required parameters, no optional parameters  
            this.SetMinParams(2);  
            this.SetMaxParams(2);  
  
            // Functoid accepts two inputs  
            AddInputConnectionType(ConnectionType.AllExceptRecord);  
            AddInputConnectionType(ConnectionType.AllExceptRecord);  
  
            // Set the output connection type  
            this.OutputConnectionType = ConnectionType.AllExceptRecord;  
  
            // Set the function name that needs to be called  
            // when this functoid is invoked.  The resulting assembly  
            // must be present in the Global Assembly Cache  
            // to ensure its availability.  
            SetExternalFunctionName(GetType().Assembly.FullName, "Microsoft.Samples.BizTalk.CustomFunctoid.CustomStringConcatFunctoid", "ConCatStrings");  
        }  
  
        // This function is executed by BizTalk to do the concatenation  
        public string ConCatStrings(string val1, string val2)  
        {  
            return val2 + val1;  
        }  
    }  
}  

See Also

Using BaseFunctoid
Developing a Custom Inline Functoid
Developing a Custom Cumulative Functoid
Custom Functoid (BizTalk Server Sample)