Creating Objects Without a Model in C#

Introduction

In C#, a model usually refers to a strongly typed class that represents structured data (for example, a DTO, entity, or domain object). However, there are many scenarios where you may want to create objects without defining a formal model class:

• Rapid prototyping

• Handling dynamic or unknown data shapes (JSON, configuration, metadata)

• Reducing boilerplate for small or temporary data structures

• Interacting with dynamic APIs

This article explains the best technical approaches to creating objects without a model in C#, with examples, pros, cons, and guidance on when to use each approach.

1. Anonymous Types (Best for Local, Read-Only Data)

Overview

Anonymous types allow you to create an object without defining a class, directly inline in your code. The compiler generates a temporary type for you.

Example

var user = new
{
    Id = 1,
    Name = "Alice",
    IsActive = true
};

Console.WriteLine(user.Name);

Characteristics

• Properties are read-only

• Type is known only at compile time

• Scope is limited (method-level usage)

Pros

Very concise and readable
Strongly typed (compile-time safety)
No class definition required

Cons

Cannot return from public methods easily
Cannot modify properties
Not suitable for complex logic or reuse

Best Use Cases

• LINQ projections

• Temporary data grouping

• Local calculations

2. dynamic Objects (Best for Runtime Flexibility)

Overview

The dynamic keyword defers type checking to runtime, allowing you to add or change properties dynamically.

Example

dynamic user = new ExpandoObject();
user.Id = 1;
user.Name = "Bob";
user.IsActive = true;

Console.WriteLine(user.Name);

Required Namespace

using System.Dynamic;

Pros

Extremely flexible
Properties can be added/removed at runtime
Ideal for JSON or loosely typed data

Cons

No compile-time safety
Runtime errors possible
Slower performance than strongly typed objects

Best Use Cases

• Consuming dynamic APIs

• JSON parsing without schemas

• Plugin or scripting systems

3. Dictionary<string, object> (Best for Data-Driven Scenarios)

Overview

Using a dictionary allows you to store key-value pairs where values can be of any type.

Example

var user = new Dictionary<string, object>
{
    { "Id", 1 },
    { "Name", "Charlie" },
    { "IsActive", true }
};

Console.WriteLine(user["Name"]);

Pros

Simple and explicit
Fully dynamic structure
Easy to serialize/deserialize

Cons

No IntelliSense support
Manual casting required
Error-prone for large datasets

Best Use Cases

• Metadata storage

• Configuration systems

• Key-value based processing

4. Tuples (Best for Small, Structured Data)

Overview

Tuples provide a lightweight way to group multiple values without a model class.

Example

var user = (Id: 1, Name: "Diana", IsActive: true);

Console.WriteLine(user.Name);

Pros

Lightweight and fast
Named fields improve readability
Compile-time type safety

Cons

Not expressive for complex domains
Limited scalability
Not suitable for APIs or persistence

Best Use Cases

• Returning multiple values from a method

• Small data transfers

• Performance-sensitive code

5. JSON-Based Objects (JsonElement / JObject)

Overview

When working with JSON-heavy systems, you can manipulate objects without defining models using JSON APIs.

Example (System.Text.Json)

using System.Text.Json;

string json = "{ \"Id\": 1, \"Name\": \"Eva\" }";
JsonElement user = JsonSerializer.Deserialize<JsonElement>(json);

Console.WriteLine(user.GetProperty("Name").GetString());

Pros

Ideal for schema-less data
No model maintenance
Common in microservices

Cons

Verbose access syntax
Runtime errors possible
Harder to refactor

Best Use Cases

• API gateways

• Event-driven systems

• Logging and auditing

Comparison Table

Best Practice Recommendation

Use Anonymous Types when:

• Data is local and temporary

• You need strong typing

Use Tuples when:

• Returning multiple simple values

• Performance matters

Use dynamic / ExpandoObject when:

• Structure is unknown at compile time

• You control runtime validation

Avoid dynamic approaches when:

• Business logic is complex

• Long-term maintenance is required

Rule of Thumb: If the data structure is stable and reused, create a model class. If it is temporary or dynamic, choose one of the approaches above.

Conclusion

Creating objects without a model in C# is powerful when used correctly. Each technique has trade-offs between flexibility, safety, and maintainability. Choosing the right approach depends on scope, lifetime, and reliability requirements.

For production systems, prefer strongly typed models. For short-lived, dynamic, or exploratory code, the approaches above provide clean and efficient alternatives.