Bind DBContext object with Model on .Net Core-CodePudding

I have a model class which looks like below-

public class ProductsViewModel
{
        public int ProductId { get; set; }
        public string ProductName { get; set; }
        public bool IsActive{ get; set; }
}

Also have below db Context

    [Table("Products")]
    public partial class Products
    {    
        [Column("ProductId")]
        public int ProductId { get; set; }
        [Column("ProductName")]
        public string ProductName{ get; set; }
        [Column("IsActive")]
        public bool IsActive { get; set; }
    }

I am fetching the result using below LINQ query, which is returning correct data.

List<Products> productData = _context.Products.Where(x => x.IsActive == true).ToList();

Now, I want to bind this data i.e productData with my model.. something similat to ProductsViewModel = productData .
I know I can loop through productData records and assign values to model properties but I am looking for a direct way to map these two. Is there any quick wat to get all the productData assigned to my model?

CodePudding user response：

You can use a mapping framework, the one I use the most is Automapper https://docs.automapper.org/en/stable/Getting-started.html.

 public class AClass {
      private readonly IMapper _mapper;
      private readonly ADbContext _dbContext;

      public AClass (IMapper mapper, ADBContext dbContext)
      {
          _mapper = mapper;
          _dbContext = dbContext;
      }

      public async Task<IEnumerable<ProductViewModel>> AMethod()
      {
           var dbProducts = await _dbContext.Products.Where(x => x.IsActive == true).ToListAsync();
           return dbProducts.Select(x => _mapper.Map<ProductViewModel>(x))
      }
 }

CodePudding user response：

You can use Automapper for a clean mapping as stated in another answer, alternatively, for more complex mapping, you can configure AutoMapper profiles for whatever exotic mappings you need.

For a direct assignment using = it can be done by overloading the assignment operator in the ProductsViewModel class:

public class ProductsViewModel
{
    public int ProductId { get; set; }
    public string ProductName { get; set; }
    public bool IsActive { get; set; }

    public static implicit operator ProductsViewModel(Products obj)
    {
        return new ProductsViewModel()
        {
            ProductName = obj.ProductName,
            IsActive = obj.IsActive,
            ProductId = obj.ProductId,
        };
    }
}

Now your direct assignment will work fine.

For example:

var productsViewModels = _context.Products.Where(x => x.IsActive)
    .Select(x => (ProductsViewModel)x).ToList();

Or more explicitly:

var productsViewModels = _context.Products.Where(p => p.IsActive)
    .Select(x => { ProductsViewModel model = x; return model; }).ToList();

Here you have some running code you can consult for your convenience.