How to use the command 'monop' (with examples)

The monop command is a powerful tool used in the .NET ecosystem to explore the internals of .NET assemblies. It is specifically designed to find and display signatures of types and methods inside these assemblies, which is incredibly useful for developers who need to understand the structure and functionality of .NET code. Whether it’s examining built-in .NET Framework types or inspecting custom assemblies for defined types and their members, monop provides invaluable insights that can assist in development, debugging, and learning.

Use case 1: Show the structure of a Type built-in of the .NET Framework

Code:

monop System.String

Motivation:

Understanding the structure of built-in .NET Framework types is essential for developers who want to master the intricacies of .NET programming. The System.String type is fundamental and understanding its methods and properties can help in utilizing strings efficiently in applications.

Explanation:

• monop: This is the base command for inspecting .NET types.
• System.String: This specifies the type whose structure and signature details you want to see. It is a fully qualified name of the type within the .NET framework.

Example Output:

Methods of System.String
  ReturnType: System.String
  Method name: ToUpper()
  Method name: ToLower()
  Method name: Substring(int startIndex)
  ...

Use case 2: List the types in an assembly

Code:

monop -r:path/to/assembly.exe

Motivation:

When working with a complex .NET application, it is often necessary to know what types are defined in an assembly. This could be for the purposes of debugging, refactoring, or extending application functionality. Listing types provides a big-picture view of the components available within the assembly.

Explanation:

• -r:path/to/assembly.exe: This option specifies the path to the assembly file you wish to inspect. It tells monop to focus on an external assembly located at the given path in contrast to built-in .NET types.

Example Output:

Types in assembly: MyApplication.exe
  Type Name: MyApplication.Program
  Type Name: MyApplication.Helpers.MathHelper
  ...

Use case 3: Show the structure of a Type in a specific assembly

Code:

monop -r:path/to/assembly.dll Namespace.Path.To.Type

Motivation:

Sometimes, the built-in .NET types don’t meet the specific needs of your application, leading you to refer to custom types defined in your assemblies. By specifying a particular type within an assembly, you can explore its structure and understand the defined methods, properties, and other signatures.

Explanation:

• -r:path/to/assembly.dll: Similar to the previous use case, this specifies the location of the assembly file.
• Namespace.Path.To.Type: This is the fully qualified path to the specific type within the specified assembly whose structure you want to view.

Example Output:

Methods of ExampleAssembly.ExampleNamespace.ExampleType:
  ReturnType: void
  Method name: ExampleMethod(int param1)
  ...

Use case 4: Only show members defined in the specified Type

Code:

monop -r:path/to/assembly.dll --only-declared Namespace.Path.To.Type

Motivation:

Often, you need to focus on just the members that are specifically declared within a type, excluding those inherited from base classes. This can be particularly useful for developers working on highly object-oriented projects where inheritance chains are long and complex. It provides clarity on what is genuinely unique within the context of the defined type.

Explanation:

• -r:path/to/assembly.dll: Points to the external assembly.
• --only-declared: This option filters the members shown to include only those that are declared directly within the specified type.
• Namespace.Path.To.Type: This represents the target type within the assembly for which you want to display the unique members.

Example Output:

Declared Members in ExampleNamespace.ExampleType
  Method name: CustomMethod()
  Property name: CustomProperty
  ...

Use case 5: Show private members

Code:

monop -r:path/to/assembly.dll --private Namespace.Path.To.Type

Motivation:

Exploring private members of a type reveals insights into the encapsulation and internal workings of a type, which are typically hidden from external access. This exploration can be crucial during debugging, especially if you’re trying to understand how internal methods and properties are interacting without directly accessing them in your code.

Explanation:

• -r:path/to/assembly.dll: Indicates the path to the specific .NET assembly.
• --private: This flag includes private members in the output, offering more detailed insights into the type.
• Namespace.Path.To.Type: Specifies the type whose private members you wish to examine.

Example Output:

Private Members in ExampleNamespace.ExampleType
  Method name: PrivateHelperMethod(int helpLevel)
  Member name: innerData
  ...

Use case 6: Hide obsolete members

Code:

monop -r:path/to/assembly.dll --filter-obsolete Namespace.Path.To.Type

Motivation:

.NET libraries evolve over time, sometimes deprecated or obsolete members remain in codebases. Developers can use this command to filter out such obsolete members, which helps in focusing on up-to-date and relevant parts of an API when refactoring or using third-party libraries.

Explanation:

• -r:path/to/assembly.dll: Path to the .NET assembly.
• --filter-obsolete: This filters out any members marked as obsolete so you can view only relevant and current members.
• Namespace.Path.To.Type: Specifies the type from which to hide obsolete members.

Example Output:

Current Members in ExampleNamespace.ExampleType (Obsolete Hidden)
  Method name: CurrentMethod()
  ...

Use case 7: List the other assemblies that a specified assembly references

Code:

monop -r:path/to/assembly.dll --refs

Motivation:

Understanding dependencies is key to managing a .NET application’s architecture. Knowing what external assemblies a given assembly references can help in anticipating compatibility issues, optimizing performance, or preparing for deployment where full dependency management is critical.

Explanation:

• -r:path/to/assembly.dll: Specifies the assembly file for which you want to view dependencies.
• --refs: This flag lists actual dependencies of the specified assembly, allowing you to understand what other .NET assemblies it depends on, directly inside the ecosystem.

Example Output:

Referenced assemblies for ExampleAssembly.dll:
  Assembly: System.Xml
  Assembly: Newtonsoft.Json
  ...

Conclusion:

The monop command is an extremely versatile tool in the .NET developer’s toolkit. From analyzing built-in framework types to detailing custom assembly structures and dependencies, it empowers developers to gain profound insights into their codebases. Given the variety of its use cases, developers can leverage monop to improve code quality, streamline development processes, and enhance their understanding of .NET applications.