I am new to MEF and experimenting with ExportFactory. Can I use ExportFactory to create a list based on user insertion of objects? A sample would be something similar to what is shown below. I am probably not understanding the use of ExportFactory because during runtime I get an error shown below during composition.
1) No valid exports were found that match the constraint '((exportDefinition.ContractName == "System.ComponentModel.Composition.ExportFactory(CommonLibrary.IFoo)") AndAlso (exportDefinition.Metadata.ContainsKey("ExportTypeIdentity") AndAlso "System.ComponentModel.Composition.ExportFactory(CommonLibrary.IFoo)".Equals(exportDefinition.Metadata.get_Item("ExportTypeIdentity"))))', invalid exports may have been rejected.
class Program
{
static void Main(string[] args)
{
Test mytest = new Test();
}
}
public class Test : IPartImportsSatisfiedNotification
{
[Import]
private ExportFactory<IFoo> FooFactory { get; set; }
public Test()
{
CompositionInitializer.SatisfyImports(this);
CreateComponent("Amp");
CreateComponent("Passive");
}
public void OnImportsSatisfied()
{
int i = 0;
}
public void CreateComponent(string name)
{
var componentExport = FooFactory.CreateExport();
var comp = componentExport.Value;
}
}
public interface IFoo
{
double Name { get; set; }
}
[ExportMetadata("CompType", "Foo1")]
[Export(typeof(IFoo))]
[PartCreationPolicy(System.ComponentModel.Composition.CreationPolicy.NonShared)]
public class Foo1 : IFoo
{
public double Name { get; set; }
public Foo1()
{
}
}
[ExportMetadata("CompType", "Foo2")]
[Export(typeof(IFoo))]
[PartCreationPolicy(System.ComponentModel.Composition.CreationPolicy.NonShared)]
public class Foo2 : IFoo
{
public double Name { get; set; }
public Foo2()
{
}
}
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