Question

大家好日子。我在Visual Studio 2015中创建了一个Xamarin.Forms便携式应用程序。我希望我的移动应用程序能够连接到VS2015中的SQL数据库。

所以我在我的解决方案中创建了两个项目。一个用于我的移动应用程序，使用Xamarin平台，另一个用于处理Web服务和数据库。有了这个，我使用了ASP.NET WEB API 。

我希望得到任何帮助，无论我是否正在做这件事。

让我告诉你我的代码。这应该显示所有客户/客户的列表。

1。）XamarinForms（便携式）

ClientList.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
         xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
         x:Class="XamarinFormsDemo.Views.ClientListPage"
         xmlns:ViewModels="clr-namespace:XamarinFormsDemo.ViewModels;assembly=XamarinFormsDemo"
         xmlns:controls="clr-namespace:ImageCircle.Forms.Plugin.Abstractions;assembly=ImageCircle.Forms.Plugin.Abstractions"
         BackgroundImage="bg3.jpg"
         Title="Client List">


  <ContentPage.BindingContext>
    <ViewModels:CustomerVM/>
  </ContentPage.BindingContext>


<SearchBar Placeholder="Search" Text="{Binding Keyword}" SearchCommand="{Binding SearchCommand}" x:Name="txtSearch" />

<ListView ItemsSource="{Binding PlotModel, Mode=TwoWay}"
          HasUnevenRows="True"
          IsPullToRefreshEnabled="True"
          x:Name="listView">


  <ListView.ItemTemplate>
    <DataTemplate>
      <ViewCell>
        <Grid Padding="10" RowSpacing="10" ColumnSpacing="5">
          <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
          </Grid.RowDefinitions>
          <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
            <ColumnDefinition Width="*"/>
          </Grid.ColumnDefinitions>

          <controls:CircleImage Source="icon.png"
                 HeightRequest="66"
                 HorizontalOptions="CenterAndExpand"
                 Aspect="AspectFill"
                 WidthRequest="66"
                 Grid.RowSpan="2"
               />


          <Label Grid.Column="1"
                 Text="{Binding CUSTOMER_NAME}"
                 TextColor="#24e97d"
                 FontSize="24"/>



          <Label Grid.Column="1"
                  Grid.Row="1"
                   Text="{Binding CUSTOMER_CODE}"
                   TextColor="White"
                   FontSize="18"
                   Opacity="0.6"/>


          <Label Grid.Column="1"
              Grid.Row="2"
              Text="{Binding CUSTOMER_CONTACT}"
               TextColor="White"
               FontSize="18"
               Opacity="0.6"/>



        </Grid>
      </ViewCell>
    </DataTemplate>
  </ListView.ItemTemplate>

</ListView>


<StackLayout Orientation="Vertical"
         Padding="30,10,30,10"
         HeightRequest="20"
         BackgroundColor="#24e97d"
         VerticalOptions="Center"
         Opacity="0.5">
  <Label Text="© Copyright 2016   SMESOFT.COM.PH   All Rights Reserved "
         HorizontalTextAlignment="Center"
         VerticalOptions="Center"
         HorizontalOptions="Center" />
    </StackLayout>




</ContentPage>

Customer.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace XamarinFormsDemo.Models
{
    public class Customer
    { 

public int Id { get; set; }
public string CUSTOMER_CODE { get; set; }
public string CUSTOMER_NAME { get; set; }
public string CUSTOMER_EMAIL_ADDRESS { get; set; }
public string CUSTOMER_MOBILE_NUMBER { get; set; }
public string CUSTOMER_CONTACT { get; set; }
public string CUSTOMER_LANDLINE { get; set; }
public string CUSTOMER_FAX_NUMBER { get; set; }
public string ADDRESS { get; set; }
public int LOCATION_TYPE_ID { get; set; }
public int INDUSTRY_TYPE_ID { get; set; }
public int CUSTOMER_TYPE_ID { get; set; }
public int IS_DELETED { get; set; }
public DateTime DATE_CREATED { get; set; }
}
}

CustomerVM.cs

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Input;
using Xamarin.Forms;
using XamarinFormsDemo.Models;
using XamarinFormsDemo.Services;
using XamarinFormsDemo.Views;

namespace XamarinFormsDemo.ViewModels
{
    public class CustomerVM : INotifyPropertyChanged
    {


    private List<Customer> _customerList; // keep all customers
    private List<Customer> _searchedCustomerList; // keep a copy for searching
    private Customer _selectedCustomer = new Customer();

    private string _keyword = "";
    public string Keyword
    {
        get
        {
            return _keyword;
        }
        set
        {
            this._keyword = value;

            // while keyword changed we filter Employees
            //Filter();
        }
    }



    private void Filter()
    {
        if (string.IsNullOrWhiteSpace(_keyword))
        {
            CustomerList = _searchedCustomerList;

        }
        else
        {
            // var lowerKeyword = _keyword.ToLower();
            CustomerList = _searchedCustomerList.Where(r => r.CUSTOMER_NAME.ToLower().Contains(_keyword.ToLower())).ToList();
            //  EmployeesList = _searchedEmployeesList.Where(r => r.EMPLOYEE_NAME.Contains(_keyword)).ToList();


        }
    }




    public List<Customer> CustomerList
    {
        get
        {
            return _customerList;
        }
        set
        {
            _customerList = value;
            OnPropertyChanged();
        }
    }


    public ICommand SearchCommand
    {
        get
        {
            return new Command((sender) =>
            {
                //var searchBar = (SearchBar)sender;
                //this.Keyword = searchBar.Text;
                Filter();
            });
        }
    }



    public CustomerVM()
    {
        InitializeDataAsync();

    }

    private async Task InitializeDataAsync()
    {
        var customerServices = new CustomerServices();
        _searchedCustomerList = await customerServices.GetCustomerAsync();
        CustomerList = await customerServices.GetCustomerAsync();

    }


    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        var handler = PropertyChanged;
        if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
        }

    }
}

CustomerServices.cs

using Plugin.RestClient;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using XamarinFormsDemo.Models;

namespace XamarinFormsDemo.Services
{
    public class CustomerServices
{
    public async Task<List<Customer>> GetCustomerAsync()
    {
        RestClient_Customer<Customer> restClient = new RestClient_Customer<Customer>();

        var customerList = await restClient.GetCustomerAsync(); //yung getasync ay pantawag as restclient

        return customerList;
    }

    }
}

RestClient.cs

public class RestClient_Customer <T>
{


    private const string WebServiceUrl = "http://localhost:50857/api/Customer/";

    public async Task<List<T>> GetCustomerAsync()
    {
        var httpClient = new HttpClient();

        var json = await httpClient.GetStringAsync(WebServiceUrl);

        var taskModels = JsonConvert.DeserializeObject<List<T>>(json);

        return taskModels;
    }
 }

2。）WebFormsDemo

CustomerViewModel.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace WebFormsDemo.ViewModel
{
    public class CustomerViewModel
    {

    public int Id { get; set; }
    public string CUSTOMER_CODE { get; set; }
    public string CUSTOMER_NAME { get; set; }
    public string CUSTOMER_EMAIL_ADDRESS { get; set; }
    public string CUSTOMER_MOBILE_NUMBER { get; set; }
    public string CUSTOMER_CONTACT { get; set; }
    public string CUSTOMER_LANDLINE { get; set; }
    public string CUSTOMER_FAX_NUMBER { get; set; }
    public string ADDRESS { get; set; }
    public int LOCATION_TYPE_ID { get; set; }
    public int INDUSTRY_TYPE_ID { get; set; }
    public int CUSTOMER_TYPE_ID { get; set; }
    public int IS_DELETED { get; set; }
    public DateTime DATE_CREATED { get; set; }
    }
}

CustomerController.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 CustomerController : ApiController
    {
    private EBMSEntities db = new EBMSEntities();

    // GET: api/Customer
    public IQueryable<CustomerViewModel> GetCustomerViewModels()
    {
        var displaycustomerInfo = from cust in db.CUSTOMERs
                                  select new CustomerViewModel
                                  {
                                      Id = cust.CUSTOMER_ID,
                                      CUSTOMER_CODE = cust.CUSTOMER_CODE,
                                      CUSTOMER_NAME = cust.CUSTOMER_NAME,
                                      CUSTOMER_MOBILE_NUMBER = cust.CUSTOMER_MOBILE_NUMBER,
                                      CUSTOMER_EMAIL_ADDRESS = cust.CUSTOMER_EMAIL_ADDRESS,
                                      CUSTOMER_CONTACT = cust.CUSTOMER_EMAIL_ADDRESS + "," + " " + cust.CUSTOMER_MOBILE_NUMBER
                                  };




        return displaycustomerInfo;
    }        
    }
}

如您所见，我的RestClient仅使用WebService URL访问WebFormsDemo中CustomerController.cs的内容。

说完所有这些之后，我仍然无法连接或显示这两个项目。我做对了吗？请帮我。非常感谢。

Answer 1

原因是因为它没有获得您的服务的任何数据，而是使用它

 public interface ICustomer
  {
       Task<string> GetCustomers();
  }

  public class ICustomerService : ICustomer
  {

    public async Task<string> GetCustomers()
    {
      var client = new HttpClient();
      var response = await client.GetAsync(string.Format("http://mysite/api/Customer"));
      var responseString = await response.Content.ReadAsStringAsync();
      return responseString; 
    }

   }

Xamarin.Forms使用Web服务连接到数据库

1 个答案: