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ControllerBase

ControllerBase

Microsoft.AspNetCore.Mvc

Represents a base class for MVC controllers that do not perform view rendering. This class provides core functionality for handling HTTP requests, including action execution, model binding, and authorization.

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Example
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Description

ControllerBase is a fundamental class in ASP.NET Core MVC for building web APIs. It offers a lightweight foundation for controllers that primarily return data (like JSON or XML) rather than rendering HTML views. It includes essential features such as:

  • Action execution pipeline management
  • Model binding and validation
  • Authorization and authentication
  • Result execution
  • Dependency Injection integration

By inheriting from ControllerBase, you can create controllers that are focused on handling API endpoints without the overhead of view rendering capabilities, leading to more efficient and specialized API implementations.

Properties

Name Type Description
ControllerContext ControllerContext Gets or sets the context information for the controller.
HttpContext HttpContext Gets the HttpContext for the current request.
Request HttpRequest Gets the HttpRequest for the current request.
Response HttpResponse Gets the HttpResponse for the current request.
ModelState ModelStateDictionary Gets a dictionary that contains the state of the model binding and validation process.

Methods

Name Signature Description
Ok IActionResult Ok(object value) Returns an Ok (200) response with the specified value.
BadRequest IActionResult BadRequest(object error) Returns a Bad Request (400) response with the specified error.
NotFound IActionResult NotFound() Returns a Not Found (404) response.
CreatedAtAction IActionResult CreatedAtAction(string actionName, object routeValues, object value) Returns a Created At Action (201) response.
Ok IActionResult Ok() Returns an Ok (200) response.

C# Example

using Microsoft.AspNetCore.Mvc;

namespace MyApi.Controllers
{
    [ApiController]
    [Route("api/[controller]")]
    public class ProductsController : ControllerBase
    {
        [HttpGet]
        public IActionResult GetAllProducts()
        {
            // In a real application, you would fetch products from a database
            var products = new[]
            {
                new { Id = 1, Name = "Laptop" },
                new { Id = 2, Name = "Keyboard" }
            };
            return Ok(products); // Returns 200 OK with the product data
        }
        
        [HttpPost]
        public IActionResult CreateProduct([FromBody] Product newProduct)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState); // Returns 400 Bad Request if model state is invalid
            }
            
            // In a real application, you would save the newProduct to the database
            newProduct.Id = 3; // Assign an ID
            
            return CreatedAtAction(nameof(GetProductById), new { id = newProduct.Id }, newProduct); // Returns 201 Created
        }
        
        [HttpGet("{id}")]
        public IActionResult GetProductById(int id)
        {
            // In a real application, you would fetch the product from a database
            var product = new { Id = id, Name = "Sample Product" };
            
            if (product == null)
            {
                return NotFound(); // Returns 404 Not Found
            }
            
            return Ok(product); // Returns 200 OK
        }
    }
    
    // A simple model class for demonstration
    public class Product
    {
        public int Id { get; set; }
        public string Name { get; set; }
    }

VB.NET Example