SSIS Custom Data Flow Component - Variable Type Converter

Hi all,



I am creating a customer data flow component for SSIS for use in a package. I've got some custom properties that I am exposing using the supplied advanced editor (no custom property editor here).



Some of my properties are enumerated types, and I have deciphered how to get those properties to show as dropdown lists of their respective enumerations. (For those of you who may be looking as hard as I did as to how to accomplish this, see the end of this post.)



I also have a few properties which request SSIS package variable names - such as an file name variable. However, I can't figure out how to tell the advanced editor that the property is looking for an SSIS variable, so that it can show a dropdown list of package variables, much like virtually any other Microsoft supplied Data Flow component can.



Is there a Type Converter I could specify for those custom properties? Is there another way to instruct SSIS that my custom property is expecting a variable? Or do I need to code a custom UI for editing my Data Flow Task?



To create a dropdown list of values for a custom property that represents an enum, do the following:

1. Create your enum definition, such as "public enum ThisIsMyEnum { one, two }"

2. Create a new class that inherits from TypeConverter, such as "public class MyEnumConverter : TypeConverter"

3. Override "CanConvertFrom", and return true if "sourceType == typeof(string)"

4. Override "CanConvertTo", and return true if "destinationType == typeof(string)"

5. Override "ConvertFrom", and return the enum value (such as "one" or "two" in my example) that corresponds to the string passed in the parameter "value"

6. Override "ConvertTo", and return a string that corresponds to the enum value passed in the parameter "value"

7. Override "GetStandardValuesSupported" and return true

8. Override "GetStandarValuesExclusive" and return true to indicate that ONLY the enum values should be accepted

9. Override "GetStandardValues", and return a new StandardValuesCollection constructed with Enum.GetValues() of your enum, such as "return new StandardValuesCollection(Enum.GetValues(typeof(ThisIsMyEnum)));"

10. Just above your "public enum" declaration, add a "TypeConverter" attribute to link your type converter to your enum, such as "[TypeConverter(typeof(MyEnumConverter))]"

11. In "ProvideComponentProperties", after you've created your custom property like this: "IDTSCustomProperty90 propEnum = ComponentMetaData.CustomPropertyCollection.New()", add another line to specify the TypeConverter property of the property to the full assembly name of your type converter, like so: "propEnum.TypeConverter = typeof(MyEnumConverter).AssemblyQualifiedName;"