在 ASP.NET Core Web API 中的 HttpGet 方法中返回模型的单个属性

Question

我必须 return ASP.NET Core API 中的 GetAll() 方法中的单个模型属性。这是我的模型：

using System;
using System.Collections.Generic;

namespace ProjectWayneAPI.Models
{
public partial class Consignment
{

    public Guid Id { get; set; }
    public DateTime? DateCreated { get; set; }
    public bool? Deleted { get; set; }
    public string CustomerReference { get; set; }
    public string ConsignmentNote { get; set; }
    public Guid AccountId { get; set; }
    public Guid BookedByUser { get; set; }
    public string DescriptionToLeave { get; set; }

    public virtual Account Account { get; set; }
    public virtual User BookedByUserNavigation { get; set; }
    public virtual User CheckedByUserNavigation { get; set; }
    public virtual User ModifiedByUserNavigation { get; set; }
    public virtual User QuotedByUserNavigation { get; set; }
}

}

我必须 return 在我的控制器的方法中只有 ConsignmentNote（但我必须拉出所有的）。

这是我的控制器：

[Route("api/[controller]")]
[ApiController]
public class ConsignmentsController : ControllerBase
{
    private readonly WayneContext _context;

    public ConsignmentsController(WayneContext context)
    {
        _context = context;
    }

    //GET: api/Consignment Notes
    [Route("[connote]")]
    [HttpGet]
    public async Task<ActionResult<IEnumerable<Consignment>>> GetConsignmentNote()
    {
        var connote = await _context.Consignment
            .Include(x => x.ConsignmentNote)
            .ToListAsync();
        return connote;
    }
    // GET: api/Consignments
    [HttpGet]
    public async Task<ActionResult<IEnumerable<Consignment>>> GetConsignment()
    {
        var consignments = await _context.Consignment
            .Where(c => c.Deleted == false)
            .Include(bu=> bu.BookedByUserNavigation)
            .ToListAsync();
        return consignments; 
    }
}

我必须 return 使用此方法 public 异步任务>> GetConsignmentNote() 的所有含义，如果您检查方法，该查询是 returning 异常。还有在这种情况下如何覆盖 [HttpGet]？

Answer 1

嗨，如果你尝试这样的事情怎么办：

//[Route("[connote]")] < --remove route and call your method GET to verride httpget .. it will match the api/Consignments [GET]
    //[HttpGet]
    public async Task<ActionResult<IEnumerable<ConsignmentNote>>> Get()
    {
        var connote = await _context.Consignment
            .Include(x => x.ConsignmentNote)
            .ToListAsync();
        return connote.Select(xx=>xx.ConsignmentNote).ToList();
    }

希望对你有帮助！！

Answer 2

Include用于include related properties（即您的导航属性，例如Account）而不用于select正常属性的子集，如 ConsignmentNote。

如果你想要的只是 ConsignmentNote 属性那么你应该 Select 一个新的 Consignment 并且只填充那个特定的属性:

var connote = await _context.Consignment
                            .Select(x => new Consignment 
                             { 
                                ConsignmentNote = x.ConsignmentNote
                             })
                            .ToListAsync();
return connote; // List<Consignment>

但请注意，这仍然是 select 一个 大部分为空的对象 。如果您想要的只是一个仅包含 string 值的列表，那么您可以通过 select 直接属性并更改 select 来实现。 =32=]类型：

public async Task<ActionResult<IEnumerable<string>>> GetConsignmentNote() 
{
    var connote = await _context.Consignment
                                .Select(x =>  x.ConsignmentNote)
                                .ToListAsync();
    return connote; // List<string>
}

在 ASP.NET Core Web API 中的 HttpGet 方法中返回模型的单个属性

Returning a single property of a Model in HttpGet Method in ASP.NET Core Web API

c#

linq

asp.net-core

asp.net-core-webapi

ef-core-3.1

在 ASP.NET Core Web API 中的 HttpGet 方法中返回模型的单个 属性

Returning a single property of a Model in HttpGet Method in ASP.NET Core Web API

c#

linq

asp.net-core

asp.net-core-webapi

ef-core-3.1

在 ASP.NET Core Web API 中的 HttpGet 方法中返回模型的单个属性