ILMerge.Fody is an add-in for Fody

This add-in merges the referenced types of local dependencies as private types into the target assembly, and removes the references to the local dependencies. This can help you to e.g. escape the DLL-hell.

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NuGet installation

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

PM> Install-Package ILMerge.Fody
PM> Update-Package Fody

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

Add to FodyWeavers.xml

Add <ILMerge/> to FodyWeavers.xml

<?xml version="1.0" encoding="utf-8" ?>
<Weavers>
  <ILMerge />
</Weavers>

How it works

Merge IL code from referenced assemblies into the main assembly

This weaver was inspired by the ILMerge Tool by Mike Barnett from Microsoft.

Beside the simplified usage as a Fody add in, it was designed for a slightly different usage:

• It does not merge complete assemblies, but only the types that are used. This will save a lot of space if you use only some parts of a larger library.
• It hides the merged types by making them private, avoiding conflicts with other modules using the same code.

This way you can make use of 3rd party libraries, without exposing them as references that you have to ship separately. You will also avoid the so called "dll hell", since all the code is now private in your assembly.

Details

This Task performs the following changes

• Take all assemblies that have been marked as "Copy Local" and merges the IL code into the target assembly.
• Removes the references to the assemblies that have been merged.

.NET Core support

Since .NET Core projects do not mark references as "Copy Local", ILMerge.Fody will instead try to merge all references. Make sure to use the configuration options to exclude system libraries from being merged!

Configuration Options

All config options are accessed by modifying the ILMerge node in FodyWeavers.xml, or adding the corresponding attribute to the assembly, where an attribute in the assembly has precedence of the setting in the FodyWeavers.xml

Default FodyWeavers.xml:

<Weavers>
  <ILMerge />
</Weavers>

Options can be written in attribute or element form, or as an attribute in code:

As an XML element:

<ILMerge>
  <ExcludeAssemblies>xunit|newtonsoft</ExcludeAssemblies>
</ILMerge>

Or as an XML attribute:

<ILMerge ExcludeAssemblies='xunit|newtonsoft' />

Or as an attribute in code:

[assembly: ILMerge.ExcludeAssemblies("xunit|newtonsoft")]

ExcludeAssemblies

A regular expression matching the assembly names to exclude from merging.

Do not include .exe or .dll in the names.

e.g.

<ILMerge ExcludeAssemblies='xunit|newtonsoft' />

IncludeAssemblies

A regular expression matching the assembly names to include in merging.

Do not include .exe or .dll in the names.

If combined with ExcludeAssemblies, it will only apply to items not already excluded.

e.g.

<ILMerge IncludeAssemblies='My.*Module|My.*Task' />

ExcludeResources

A regular expression matching the resource names to exclude from merging.

Resource names are case sensitive.

e.g.

<ILMerge ExcludeResources='\.resources$' />

IncludeResources

A regular expression matching the resource names to include in merging.

Resource names are case sensitive.

If combined with ExcludeResources, it will only apply to items not already excluded.

e.g.

<ILMerge IncludeResources='\.resources$' />

HideImportedTypes

A switch to control whether the imported types are hidden (made private) or keep their visibility unchanged. Default is 'true'

e.g.

<ILMerge HideImportedTypes='false' />

NamespacePrefix

A string that is used as prefix for the namespace of the imported types.

e.g.

<ILMerge NamespacePrefix='$_' />

FullImport

A switch to control whether to import the full assemblies or only the referenced types. Default is 'false'

e.g.

<ILMerge FullImport='true' />

CompactMode

A switch to enable compacting of the target assembly by skipping properties, events and unused methods. Default is 'false'

e.g.

<ILMerge CompactMode='true' />