从通用 Windows 平台 (UWP) 应用向 Azure 通知中心发送通知

Question

正如标题所示，我需要向我的 Azure 中心发送通知FROM一个 UWP 应用（用 C# 编写）（然后从那里发送到我已经创建的 Android 应用）。我显然使用 GCM 向我的 Android 应用发送推送通知。

经过无数小时的搜索，我还没有找到一个有用的教程，因为他们中的大多数使用控制台应用程序来发送通知，而不是通用 Windows 平台应用程序。

如果有人可以帮助我，我会真的感激不尽。

Answer 1

您可以使用通知中心 REST API 通过普通 HTTP/HTTPS 从任何地方（后端或设备）推送通知。

这里有一个示例（使用 Java 客户端）：https://msdn.microsoft.com/en-us/library/azure/dn495628.aspx

API 参考在这里：https://msdn.microsoft.com/en-us/library/azure/dn495827.aspx

Answer 2

我将在这里回答我自己的问题，因为很多人都像我一样为此苦苦挣扎。下面的代码通过 Azure 通知中心将通知从通用 Windows 平台 (UWP) 发送到 Android 应用程序（使用 GCM）。

请注意，必须稍微更改代码才能在您自己的通知中心上运行（有关详细信息，请参阅代码中的 cmets）

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Runtime.InteropServices.WindowsRuntime;
using System.Text;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.Security.Cryptography;
using Windows.Security.Cryptography.Core;
using Windows.Storage.Streams;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;


namespace SendNotification
{
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
            this.sendNotification();
        }

        string Endpoint = "";
        string SasKeyName = "";
        string SasKeyValue = "";

        public void ConnectionStringUtility(string connectionString)
        {
            //Parse Connectionstring
            char[] separator = { ';' };
            string[] parts = connectionString.Split(separator);
            for (int i = 0; i < parts.Length; i++)
            {
                if (parts[i].StartsWith("Endpoint"))
                    Endpoint = "https" + parts[i].Substring(11);
                if (parts[i].StartsWith("SharedAccessKeyName"))
                    SasKeyName = parts[i].Substring(20);
                if (parts[i].StartsWith("SharedAccessKey"))
                    SasKeyValue = parts[i].Substring(16);
            }
        }


        public string getSaSToken(string uri, int minUntilExpire)
        {
            string targetUri = Uri.EscapeDataString(uri.ToLower()).ToLower();

            // Add an expiration in seconds to it.
            long expiresOnDate = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
            expiresOnDate += minUntilExpire * 60 * 1000;
            long expires_seconds = expiresOnDate / 1000;
            String toSign = targetUri + "\n" + expires_seconds;

            // Generate a HMAC-SHA256 hash or the uri and expiration using your secret key.
            MacAlgorithmProvider macAlgorithmProvider = MacAlgorithmProvider.OpenAlgorithm(MacAlgorithmNames.HmacSha256);
            BinaryStringEncoding encoding = BinaryStringEncoding.Utf8;
            var messageBuffer = CryptographicBuffer.ConvertStringToBinary(toSign, encoding);
            IBuffer keyBuffer = CryptographicBuffer.ConvertStringToBinary(SasKeyValue, encoding);
            CryptographicKey hmacKey = macAlgorithmProvider.CreateKey(keyBuffer);
            IBuffer signedMessage = CryptographicEngine.Sign(hmacKey, messageBuffer);

            string signature = Uri.EscapeDataString(CryptographicBuffer.EncodeToBase64String(signedMessage));

            return "SharedAccessSignature sr=" + targetUri + "&sig=" + signature + "&se=" + expires_seconds + "&skn=" + SasKeyName;
        }


        public async void sendNotification()
        {
            //insert your HubFullAccess here (a string that can be copied from the Azure Portal by clicking Access Policies on the Settings blade for your notification hub)
            ConnectionStringUtility("YOURHubFullAccess"); 

            //replace YOURHUBNAME with whatever you named your notification hub in azure 
            var uri = Endpoint + "YOURHUBNAME" + "/messages/?api-version=2015-01";
            string json = "{\"data\":{\"message\":\"" + "Hello World!" + "\"}}";


            //send an HTTP POST request
            using (var httpClient = new HttpClient())
            {
                var request = new HttpRequestMessage(HttpMethod.Post, uri);
                request.Content = new StringContent(json);

                request.Headers.Add("Authorization", getSaSToken(uri, 1000));
                request.Headers.Add("ServiceBusNotification-Format", "gcm");
                var response = await httpClient.SendAsync(request);
                await response.Content.ReadAsStringAsync();
            }
        }
    }
}