Adds an empty constructor to classes even if you have a non-empty one defined.

See Milestones for release notes.

It is expected that all developers using Fody become a Patron on OpenCollective. See Licensing/Patron FAQ for more information.

See also Fody usage.

Install the EmptyConstructor.Fody NuGet package and update the Fody NuGet package:

PM> Install-Package Fody
PM> Install-Package EmptyConstructor.Fody

The Install-Package Fody is required since NuGet always defaults to the oldest, and most buggy, version of any dependency.

Add <EmptyConstructor/> to FodyWeavers.xml

<Weavers>
  <EmptyConstructor/>
</Weavers>

If for some reason you want to skip a specific class you can mark it with a DoNotVirtualizeAttribute.

Since no reference assembly is shipped with Virtuosity. Just add the below class to your assembly. Namespace does not matter.

public class DoNotVirtualizeAttribute : Attribute
{
}

So your class will look like this

[DoNotVirtualize]
public class ClassToSkip
{
    ...
}

These config options are access by modifying the EmptyConstructor node in FodyWeavers.xml

The visibility to use when injecting constructors.

Can not be defined with Visibility.

Allowed values: public or family (aka protected)

Defaults to public.

For example

<EmptyConstructor Visibility='family'/>

Optionally the visibility of already existing constructors can be increased. If this feature is enabled, the visibility of empty-constructors of non-abstract types will be increased to the same visibility as defined by the Visibility configuration (see above).

For example

<EmptyConstructor MakeExistingEmptyConstructorsVisible='True'/>

Will ensure all constructors on non-abstract types will be public.

A list of namespaces to exclude.

Can not be defined with IncludeNamespaces.

Can take two forms.

As an element with items delimited by a newline.

<EmptyConstructor>
    <ExcludeNamespaces>
        Foo
        Bar
    </ExcludeNamespaces>
</EmptyConstructor>

Or as a attribute with items delimited by a pipe |.

<EmptyConstructor ExcludeNamespaces='Foo|Bar'/>

A list of namespaces to include.

Can not be defined with ExcludeNamespaces.

Can take two forms.

As an element with items delimited by a newline.

<EmptyConstructor>
    <IncludeNamespaces>
        Foo
        Bar
    </IncludeNamespaces>
</EmptyConstructor>

Or as a attribute with items delimited by a pipe |.

<EmptyConstructor IncludeNamespaces='Foo|Bar'/>

By default, the generated constructors remain empty. If you would like field & property initialization to be copied from an existing constructor enable this via the PreserveInitializers attribute.

<EmptyConstructor PreserveInitializers='true'/>

Example, without initializers preservation:

public class Foo
{
    private int someValue;
    private int otherValue;
        
    public Foo(int someValue)
    {
        this.someValue = someValue;
        otherValue = 17;
    }
        
    // generated constructor
    public Foo() { }
}

Example, with initializers preservation:

public class Foo
{
    private int someValue;
    private int otherValue;
        
    public Foo(int someValue)
    {
        this.someValue = someValue;
        otherValue = 17;
    }
        
    // generated constructor
    public Foo()
    {
        // note: this.someValue isn't set
        otherValue = 17;
    }
}

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