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Xamarin.Forms - Bing News Search Using Cognitive Service

In this article, you will learn how to search News using the Bing Search API Cognitive Service in Xamarin.Forms.

Introduction
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
Before starting, you can go through the following URL for an overview of Bing Web Search.
Xamarin.Forms code runs on multiple platforms - each of which has its own filesystem. This means that reading and writing files is most easily done using the native file APIs on each platform. Alternatively, embedded resources are a simpler solution to distribute data files with an app.
 
Cognitive Services
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
Xamarin and Cognitive Services together can infuse your apps, websites, and bots with intelligent algorithms to see, hear, speak, understand and interpret your user needs through natural methods of communication. Also, they help you transform your business with AI today.
 
Use AI to solve business problems
  • Vision
  • Speech
  • Knowledge
  • Search
  • Language
Bing News Search API
  1. Bing News Search API provides an experience similar to Bing News.
  2. Bing News Search API lets you send a search query to Bing and get back a list of relevant News from the Bing News Search API.
Prerequisites
  • Visual Studio 2017 or Later(Windows or Mac)
  • Bing Search API Key
Setting up a Xamarin.Forms Project
 
Start by creating a new Xamarin.Forms project. You’ll learn more by going through the steps yourself.
 
Visual Studio 2019 has more options in the opening window. Clone or check out the code from any repository or, open a project or solution for your computer.
 
Now, you need to click "Create a new project".
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
Now, filter by Project Type: Mobile
 
Choose the Mobile App (Xamarin. forms) project under C# and Mobile.
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
Name your app. You probably want your project and solution to use the same name as your app. Put it on your preferred location for projects and click "Create".
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
Now, select the blank app and target platforms - Android, iOS and Windows (UWP).
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
Subsequently, go to the solution. In there, you get all the files and sources of your project (.NET Standard). Now, select XAML page and double-click to open the MainPage.Xaml page.
 
You now have a basic Xamarin.Forms app. Click the Play button to try it out.
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
Get Bing Search API Key
 
In this step, get Bing Search API Key. Go to the following link.
 
https://azure.microsoft.com/en-in/services/cognitive-services/
 
Click "Try Cognitive Services for free".
 
Xamarin.Forms - Bing News Search Using Cognitive Service
 
Now, you can choose Bing Search APIs under Search APIs. Afterward, click "Get API Key".
Xamarin.Forms - Bing News Search Using Cognitive Service 
Read the terms, and select your country/region. Afterward, click "Next".
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
Now, log in using your preferred account.
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
Now, the API key is activated. You can use it now.
 
Note 
The trial key is available only for 7 days.
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
Setting up the User Interface
 
Go to MainPage.Xaml and write the following code.
 
MainPage.xaml
  1. <?xml version="1.0" encoding="utf-8" ?>  
  2. <ContentPage xmlns="http://xamarin.com/schemas/2014/forms"  
  3.              xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"  
  4.              xmlns:local="clr-namespace:XamarinCognitive"  
  5.              x:Class="XamarinCognitive.MainPage">  
  6.   
  7.     <StackLayout>  
  8.         <StackLayout>  
  9.             <StackLayout HorizontalOptions="Center" VerticalOptions="Start">  
  10.                 <Image x:Name="imgBanner" Source="banner.png" ></Image>  
  11.                 <Image Margin="0,0,0,10" x:Name="imgCognitive" HeightRequest="100" Source="cognitiveservice.png" ></Image>  
  12.                 <Label Margin="0,0,0,10" Text="Bing News Search" FontAttributes="Bold" FontSize="Large" TextColor="Gray" HorizontalTextAlignment="Center" ></Label>  
  13.                 <Entry x:Name="txtSearch" Placeholder="Type here.."></Entry>  
  14.                 <Button x:Name="btnSearch" WidthRequest="50" Text="Search" Clicked="BtnSearch_Clicked" />  
  15.                 <StackLayout HorizontalOptions="CenterAndExpand" Margin="10,0,0,10">  
  16.                     <ListView x:Name="listNews">  
  17.   
  18.                     </ListView>  
  19.                 </StackLayout>  
  20.             </StackLayout>  
  21.         </StackLayout>  
  22.     </StackLayout>  
  23.   
  24. </ContentPage>  
Click the play button to try it out.
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
NuGet Packages
 
Now, add the following NuGet Packages.
  • Newtonsoft.Json
Add Newtonsoft.Json NuGet
 
Go to Solution Explorer and select your solution. Right-click and select "Manage NuGet Packages for Solution". Search "Newtonsoft.Json" and add Package. Remember to install it for each project (.NET Standard, Android, iO, and UWP).
 
Create a Model
 
In this step, you can create a model for Deserializing your response.
 
ResponseModel.cs
  1. using System;  
  2. using System.Collections.Generic;  
  3. using System.Text;  
  4.   
  5. namespace XamarinCognitive  
  6. {  
  7.     public class ResponseModel  
  8.     {  
  9.         public string _type { getset; }  
  10.         public string readLink { getset; }  
  11.         public QueryContext queryContext { getset; }  
  12.         public int totalEstimatedMatches { getset; }  
  13.         public List<Sort> sort { getset; }  
  14.         public List<Value> value { getset; }  
  15.     }  
  16.   
  17.     public class QueryContext  
  18.     {  
  19.         public string originalQuery { getset; }  
  20.         public bool adultIntent { getset; }  
  21.     }  
  22.   
  23.     public class Sort  
  24.     {  
  25.         public string name { getset; }  
  26.         public string id { getset; }  
  27.         public bool isSelected { getset; }  
  28.         public string url { getset; }  
  29.     }  
  30.   
  31.     public class Thumbnail  
  32.     {  
  33.         public string contentUrl { getset; }  
  34.         public int width { getset; }  
  35.         public int height { getset; }  
  36.     }  
  37.   
  38.     public class Image  
  39.     {  
  40.         public Thumbnail thumbnail { getset; }  
  41.     }  
  42.   
  43.     public class About  
  44.     {  
  45.         public string readLink { getset; }  
  46.         public string name { getset; }  
  47.     }  
  48.   
  49.     public class Provider  
  50.     {  
  51.         public string _type { getset; }  
  52.         public string name { getset; }  
  53.     }  
  54.   
  55.     public class Value  
  56.     {  
  57.         public string name { getset; }  
  58.         public string url { getset; }  
  59.         public Image image { getset; }  
  60.         public string description { getset; }  
  61.         public List<About> about { getset; }  
  62.         public List<Provider> provider { getset; }  
  63.         public DateTime datePublished { getset; }  
  64.         public string category { getset; }  
  65.     }  
  66. }  
Bing Image Search
 
In this step, write the following code for Bing News Search.
 
MainPage.xaml.cs 
  1. using Xamarin.Forms;  
  2. using Newtonsoft.Json;  
  3. namespace XamarinCognitive  
  4. {  
  5.     public partial class MainPage : ContentPage  
  6.     {  
  7.         public static string APIKey = "d9196daefdd64a******849a759ba8861";  
  8.         public static string baseURl = "https://api.cognitive.microsoft.com/bing/v7.0/news/search";  
  9.         struct SearchResult  
  10.         {  
  11.             public String jsonResult;  
  12.             public Dictionary<String, String> relevantHeaders;  
  13.         }  
  14.         List<string> newsList = new List<string>();  
  15.         public MainPage()  
  16.         {  
  17.             InitializeComponent();  
  18.         }  
  19.   
  20.         private void BtnSearch_Clicked(object sender, EventArgs e)  
  21.         {  
  22.             SearchResult bingResult = BingNewsSearch(txtSearch.Text);  
  23.             var res = JsonConvert.DeserializeObject<ResponseModel>(bingResult.jsonResult);  
  24.             for (int i = 0; i < res.value.Count; i++)  
  25.             {  
  26.                 newsList.Add(res.value[i].name);  
  27.             }  
  28.             listNews.ItemsSource = newsList;  
  29.         }  
  30.   
  31.         //Bing News Search   
  32.         static SearchResult BingNewsSearch(string searchQuery)  
  33.         {  
  34.             var uriQuery = baseURl + "?q=" + Uri.EscapeDataString(searchQuery);  
  35.             WebRequest request = HttpWebRequest.Create(uriQuery);  
  36.             request.Headers["Ocp-Apim-Subscription-Key"] = APIKey;  
  37.             HttpWebResponse response = (HttpWebResponse)request.GetResponseAsync().Result;  
  38.             string json = new StreamReader(response.GetResponseStream()).ReadToEnd();  
  39.             var searchResult = new SearchResult();  
  40.             searchResult.jsonResult = json;  
  41.             searchResult.relevantHeaders = new Dictionary<String, String>();  
  42.             foreach (String header in response.Headers)  
  43.             {  
  44.                 if (header.StartsWith("BingAPIs-") || header.StartsWith("X-MSEdge-"))  
  45.                     searchResult.relevantHeaders[header] = response.Headers[header];  
  46.             }  
  47.             return searchResult;  
  48.         }  
  49.     }  
  50. }  
Click the Play button to try it out.
 
Xamarin.Forms - Bing News Search Using Cognitive Service 
 
I hope you have understood how to Search news using Bing Search API using Cognitive Service Bing Search API in Xamarin.Forms.
 
Thanks for reading. Please share comments and feedback. Happy Coding :)