大家好日子。我正在创建一个Xamarin.Forms便携式应用程序，其中我能够使用OxyPlot在那里显示一个饼图。
饼图包含6个切片，均为预定义。我的问题是，我将如何获得饼图，饼图基于我的数据库中的数据。
在我的 WebFormsProject 中，我创建了一个 SalesController ，其中我使用LINQ表达式来获取我需要的数据库中的所有数据。我还创建了一个 SalesViewModel ，在那里我声明了我拥有的所有属性。我尝试在我的WEB API中测试它，如果它确实返回一个值，那么它会返回一个值。
在我的PORTABLE项目中，我有一个创建的销售模型，该模型与 WebFormsProject 中的 SalesViewModel 具有完全相同的属性。我还有 SalesVM.cs ，其中我尝试使用SalesServices和RestClient访问 WebFormsProject 中的记录。
这些是我使用的代码。
的WebForms
1。） SalesViewModel.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace WebFormsDemo.ViewModel
{
public class SalesViewModel
{
public int Id { get; set; }
public int ORDER_ID { get; set; }
public int ORDER_DETAILS_ID { get; set; }
public int PRODUCT_ID { get; set; }
public string PRODUCT_CODE { get; set; }
public string NET_AMOUNT { get; set; }
}
}
2。） SalesController.cs
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using System.Web.Http.Description;
using WebFormsDemo;
using WebFormsDemo.ViewModel;
namespace WebFormsDemo.Controllers
{
public class SalesController : ApiController
{
private EBMSEntities db = new EBMSEntities();
// GET: api/Sales
public IQueryable<SalesViewModel> GetSalesViewModels()
{
//return db.SalesViewModels;
var sales = from order in db.ORDERs
join order_detail in db.ORDER_DETAILS
on order.ORDER_ID equals order_detail.ORDER_ID
join prod in db.PRODUCTs
on order_detail.PRODUCT_ID equals prod.PRODUCT_ID
orderby order_detail.TOTAL_AMT_PER_ITEM descending
//group prod by prod.PRODUCT_CODE
group order_detail by prod.PRODUCT_CODE into od
select new SalesViewModel
{
PRODUCT_CODE = od.Key,
NET_AMOUNT = od.Sum(p => p.TOTAL_AMT_PER_ITEM).ToString(),
};
return sales;
}
// GET: api/Sales/5
[ResponseType(typeof(SalesViewModel))]
public IHttpActionResult GetSalesViewModel(int id)
{
SalesViewModel salesViewModel = db.SalesViewModels.Find(id);
if (salesViewModel == null)
{
return NotFound();
}
return Ok(salesViewModel);
}
// PUT: api/Sales/5
[ResponseType(typeof(void))]
public IHttpActionResult PutSalesViewModel(int id, SalesViewModel salesViewModel)
{
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
if (id != salesViewModel.Id)
{
return BadRequest();
}
db.Entry(salesViewModel).State = EntityState.Modified;
try
{
db.SaveChanges();
}
catch (DbUpdateConcurrencyException)
{
if (!SalesViewModelExists(id))
{
return NotFound();
}
else
{
throw;
}
}
return StatusCode(HttpStatusCode.NoContent);
}
// POST: api/Sales
[ResponseType(typeof(SalesViewModel))]
public IHttpActionResult PostSalesViewModel(SalesViewModel salesViewModel)
{
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
db.SalesViewModels.Add(salesViewModel);
db.SaveChanges();
return CreatedAtRoute("DefaultApi", new { id = salesViewModel.Id }, salesViewModel);
}
// DELETE: api/Sales/5
[ResponseType(typeof(SalesViewModel))]
public IHttpActionResult DeleteSalesViewModel(int id)
{
SalesViewModel salesViewModel = db.SalesViewModels.Find(id);
if (salesViewModel == null)
{
return NotFound();
}
db.SalesViewModels.Remove(salesViewModel);
db.SaveChanges();
return Ok(salesViewModel);
}
protected override void Dispose(bool disposing)
{
if (disposing)
{
db.Dispose();
}
base.Dispose(disposing);
}
private bool SalesViewModelExists(int id)
{
return db.SalesViewModels.Count(e => e.Id == id) > 0;
}
}
}
XamarinFormsPortable
1。） Sales.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace XamarinFormsDemo.Models
{
public class Sales
{
public int Id { get; set; }
public int ORDER_ID { get; set; }
public int ORDER_DETAILS_ID { get; set; }
public int PRODUCT_ID { get; set; }
public string PRODUCT_CODE { get; set; }
public double NET_AMOUNT { get; set; }
}
}
2。） SalesVM.cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using OxyPlot;
using OxyPlot.Series;
using OxyPlot.Xamarin.Forms;
using Xamarin.Forms;
using System.Runtime.CompilerServices;
using XamarinFormsDemo.Models;
using System.Collections.ObjectModel;
using XamarinFormsDemo.Services;
namespace XamarinFormsDemo.ViewModels
{
public class SalesVM
{
private List<Sales> salesmodel { get; set; }
public List<Sales> SalesModelvm
{
get
{
return salesmodel;
}
set
{
salesmodel = value;
OnPropertyChanged();
}
}
public SalesVM()
{
InitializeDataAsync();
}
private async Task InitializeDataAsync()
{
var salesServices = new SalesServices();
SalesModelvm = await salesServices.GetSalesAsync();
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
var handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}
}
}
3.） SalesServices.cs
using Plugin.RestClient;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using XamarinFormsDemo.Models;
namespace XamarinFormsDemo.Services
{
public class SalesServices
{
public async Task<List<Sales>> GetSalesAsync()
{
RestClient_Sales<Sales> restClient = new RestClient_Sales<Sales>();
var salesList = await restClient.GetSalesAsync();
return salesList;
}
}
}
4。） RestClient.cs
public class RestClient_Sales<T>
{
private const string WebServiceUrl = "http://localhost:50857/api/Sales/";
public async Task<List<T>> GetSalesAsync()
{
var httpClient = new HttpClient();
var json = await httpClient.GetStringAsync(WebServiceUrl);
var taskModels = JsonConvert.DeserializeObject<List<T>>(json);
return taskModels;
}
}