Why is this an issue?

The AssemblyVersion attribute is used to specify the version number of an assembly. An assembly is a compiled unit of code, which can be marked with a version number by applying the attribute to an assembly’s source code file.

The AssemblyVersion attribute is useful for many reasons:

• Versioning: The attribute allows developers to track and manage different versions of an assembly. By incrementing the version number for each new release, you can easily identify and differentiate between different versions of the same assembly. This is particularly useful when distributing and deploying software, as it helps manage updates and compatibility between different versions.
• Dependency management: When an assembly references another assembly, it can specify the specific version of the dependency it requires. By using the AssemblyVersion attribute, you can ensure that the correct version of the referenced assembly is used. This helps avoid compatibility issues and ensures that the expected behavior and functionality are maintained.
• GAC management: The GAC, also known as Global Assembly Cache, is a central repository for storing shared assemblies on a system. The AssemblyVersion attribute plays a crucial role in managing assemblies in the GAC. Different versions of an assembly can coexist in the GAC, allowing applications to use the specific version they require.

If no AssemblyVersion is provided, the same default version will be used for every build. Since the version number is used by .NET Framework to uniquely identify an assembly, this can lead to broken dependencies.

How to fix it

Code examples

Noncompliant code example

using System.Reflection;

[assembly: AssemblyTitle("MyAssembly")] // Noncompliant
namespace MyLibrary
{
    // ...
}

Compliant solution

using System.Reflection;

[assembly: AssemblyTitle("MyAssembly")]
[assembly: AssemblyVersion("42.1.125.0")]
namespace MyLibrary
{
    // ...
}

Resources

Documentation

• Assembly Versioning
• Global Assembly Cache