In ASP.NET MVC, a ViewModel is a class that serves as a container for data required by a specific view. ViewModels are used to pass data from controllers to views in a structured and organized manner. They typically represent a subset of data from one or more domain models and may contain additional properties or computed values specific to the view’s requirements.
The purpose of a ViewModel includes:
Data Aggregation: ViewModels aggregate data from one or more domain models, business entities, or data sources into a single object that is tailored to the needs of a particular view.
View-Specific Data: ViewModels allow developers to shape the data in a way that aligns with the presentation requirements of the view. They can include only the properties necessary for rendering the view and exclude irrelevant data.
Enhanced Maintainability: ViewModels improve code maintainability by encapsulating view-specific logic and data transformation within a separate class. This separation of concerns makes it easier to manage and modify view-related functionality without affecting the underlying domain models.
Data Annotation and Validation: ViewModels can incorporate data annotation attributes and validation rules to enforce data integrity and validate user input before it is submitted to the server.
Reduced Coupling: ViewModels help reduce coupling between controllers and views by providing a clear contract for data exchange. Controllers interact with ViewModels rather than directly with domain models, promoting better separation of concerns and testability.
ViewModels play a crucial role in ASP.NET MVC applications by facilitating the exchange of data between controllers and views in a structured and manageable manner.
