Building RESTful Web Services with .NET Core

POST – api/Carts

Inserting data into the cart table can be done by calling the POST action, which should look like the following code block in CartsController:

// POST: api/Carts[HttpPost]public async Task<IActionResult> PostCart([FromBody] Cart cart){  if (!ModelState.IsValid)  {    return BadRequest(ModelState);  }  _context.Cart.Add(cart);  try  {    await _context.SaveChangesAsync();  }  catch (DbUpdateException)  {    if (CartExists(cart.Id))    {      return new StatusCodeResult(StatusCodes.Status409Conflict);    }    else    {      throw;    }  }  return CreatedAtAction("GetCart", new { id = cart.Id }, cart);}

The client-side function to call this action can be designed as follows:

function PostCart(customerId, productId, qty, finalPrice) {  var cart =   { Customerid: customerId, ...