在ASP.NET Web Application中通过SOAP协议调用Bing搜索服务

　　本文介绍了如何在ASP.NET Web Application中将Bing搜索作为Web Service来使用，并通过HTTP的SOAP协议在ASP.NET Web Application中调用Bing搜索功能。当然，我们也可以使用XML和JSON来调用Bing搜索服务，稍后会给出一些相关的例子。

　　本文中我将向大家演示下面这些内容：

创建一个Web Application与Bing搜索服务进行交互
添加Bing搜索服务的引用
使用Bing SourceTypes演示在线搜索功能

Bing搜索服务介绍

　　将Bing搜索功能作为Web Service来使用可以在我们的应用程序中简化许多较为复杂的功能，如创建索引、建立相关逻辑、解决数据存储等问题，本文旨从在你的应用程序中添加Bing Web Service开始。

　　什么是Web Service，想必大家都已经比较清楚了，它是Web Server上的一个程序组件，能够被客户端应用程序通过HTTP协议在Web上进行调用。有关Web Service的详细介绍，你可以查看MSDN上的文章Using ASP.NET Web Services.

　　使用Bing搜索服务你可以在你的程序中集成下列功能：

从Internet上获取有用的信息
在你的应用程序中添加广告内容
提高和增强搜索功能
查找特定位置信息
翻译条款和文本块

　　你可以通过Bing API来调用Bing Service的各种功能。上面提到的这些功能都或多或少地使用到了Bing API SourceTypes。一个SourceType是一个可以通过Bing API进行访问的信息源，有关所有这些SourceTypes的描述可以访问MSDN：About the Bing API。

先决条件

　　要完成本文中提到的这些功能，你必须具备下面这些条件：

Visual Studio 2010（稍低版本的VS也可以，如Visual Studio 2008）
能够通过SOAP协议（1.1）和HTTP协议（1.1）向服务器端发送请求
能够解析SOAP和XML

创建Web Application

　　现在我们开始展示如何创建一个Web Application并使用Bing搜索服务。

首先打开Visual Studio并创建一个普通的Web Application工程。如果你使用的是Visual Studio 2010，建议创建ASP.NET Empty Web Application类型的工程。　　　　然后我们需要在工程中添加Bing Search Service的Web引用。我们通过Web Service发现程序以获得Web服务的位置和描述信息，在Visual Studio中，Web Service发现程序是一个WSDL（Web Services Description Language）格式的XML文件，用来从Web站点中找到Web服务的描述信息。当我们在工程中添加Web引用时，Visual Studio会生成一个代理类，用来提供Web服务的本地描述，从而允许客户端代码可以直接调用Web Service提供的功能。你可以通过代理类来调用Web Service提供的方法，代理类会负责在客户端应用程序和Web Service之间进行通信。下面是在Visual Studio中添加Web引用到Web Application的步骤：

　　打开Solution Explorer，右键点击项目名称，在弹出的上下文菜单中选择Add Web Reference。

　　在弹出的对话框中输入http://api.search.live.net/search.wsdl，点击Go。

　　如果连接成功，你应该会看到有一个服务“search”被找到，点击Add Rederence按钮添加该Web引用到工程中。

　　浏览Solution Explorer面板，你会发现多了一个Web Reference文件夹，里面有live search service的API，双击它可以在Object Browser窗口中查看命名空间和对象。

　　同时，Web.config文件也会被修改，其中包含了soap.asmx服务的引用地址，如：

<applicationSettings>
    <BingSearchDemo.Properties.Settings>
        <setting name="BingSearchDemo_net_live_search_api_LiveSearchService"
            serializeAs="String">
            <value>http://api.search.live.net:80/soap.asmx</value>
        </setting>
    </BingSearchDemo.Properties.Settings>
</applicationSettings>

使用Bing ServiceTypes进行搜索

　　我们可以选择不同的Bing ServiceType进行在线搜索，下面是两种比较简单的应用类型：

Web：从Internet获取信息。
Phonebook：查找特定位置信息。

　　如何选择ServiceType呢？在BingSearchDemo.net.live.search.api命名空间下可以找到SourceType枚举对象，它下面包含了所有可能的SourceType枚举类型，如Ad、Image、InstantAnswer、MoibleWeb、News、Phonebook、QueryLocation、RelatedSearch、Showtimes、Spell、Translation、Video、Weather、Web、XRank。下面有两个类，分别使用SourceType.Web类型和SourceType.Phonebook类型：

UsingWebCourceType

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Xml;
using BingSearchDemo.net.live.search.api;

namespace BingSearchDemo
{
    public class UsingWebSourceType
    {
        // Replace the following string with the AppId you received from the
        // Bing Developer Center.
        const string AppId = "0C6C67B56FCE6E3C401882E9A7BAE196062FF144";

        public static SearchResponse PerformLiveSearch()
        {
            // LiveSearchService implements IDisposable.
            using (LiveSearchService service = new LiveSearchService())
            {
                SearchResponse response = new SearchResponse();
                try
                {
                    SearchRequest request = BuildRequest();
                    // Send the request; display the response.
                    response = service.Search(request);
                }
                catch (System.Web.Services.Protocols.SoapException ex)
                {
                    // A SOAP Exception was thrown. Display error details.
                    DisplayErrors(ex.Detail);
                }
                catch (System.Net.WebException ex)
                {
                    // An exception occurred while accessing the network.
                    HttpContext.Current.Response.Write(ex.Message);
                }
                return response;
            }
        }

        public static SearchRequest BuildRequest()
        {
            SearchRequest request = new SearchRequest();
            // Common request fields (required)
            request.AppId = AppId;
            request.Query = "msdn blogs";
            request.Sources = new SourceType[] { SourceType.Web };
            // Common request fields (optional)
            request.Version = "2.0";
            request.Market = "en-us";
            request.Adult = AdultOption.Moderate;
            request.AdultSpecified = true;
            request.Options = new SearchOption[] { SearchOption.EnableHighlighting };
            // Web-specific request fields (optional)
            request.Web = new WebRequest();
            request.Web.Count = 10;
            request.Web.CountSpecified = true;
            request.Web.Offset = 0;
            request.Web.OffsetSpecified = true;
            request.Web.Options = new WebSearchOption[] { WebSearchOption.DisableHostCollapsing, WebSearchOption.DisableQueryAlterations };
            return request;
        }

        static void DisplayErrors(XmlNode errorDetails)
        {
            // Add the default namespace to the namespace manager.
            XmlNamespaceManager nsmgr = new XmlNamespaceManager(errorDetails.OwnerDocument.NameTable);
            nsmgr.AddNamespace("api", "http://schemas.microsoft.com/LiveSearch/2008/03/Search"); XmlNodeList errors = errorDetails.SelectNodes("./api:Errors/api:Error", nsmgr);

            if (errors != null)
            {
                // Iterate over the list of errors and display error details.
                HttpContext.Current.Response.Write("Errors");
                foreach (XmlNode error in errors)
                {
                    foreach (XmlNode detail in error.ChildNodes)
                    {
                        HttpContext.Current.Response.Write(detail.Name + ": " + detail.InnerText);
                    }
                }
            }
        }
    }
}

UsingPhonebookSourceType

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using BingSearchDemo.net.live.search.api;
using System.Xml;

namespace BingSearchDemo
{
    public class UsingPhonebookSourceType
    {
        // Replace the following string with the AppId you received from the
        // Bing Developer Center.
        const string AppId = "0C6C67B56FCE6E3C401882E9A7BAE196062FF144";

        public static SearchResponse PerformLiveSearch()
        {
            // LiveSearchService implements IDisposable.
            using (LiveSearchService service = new LiveSearchService())
            {
                SearchResponse response = new SearchResponse();
                try
                {
                    SearchRequest request = BuildRequest();
                    // Send the request; display the response.
                    response = service.Search(request);
                }
                catch (System.Web.Services.Protocols.SoapException ex)
                {
                    // A SOAP Exception was thrown. Display error details.
                    DisplayErrors(ex.Detail);
                }
                catch (System.Net.WebException ex)
                {
                    // An exception occurred while accessing the network.
                    HttpContext.Current.Response.Write(ex.Message);
                }
                return response;
            }
        }

        public static SearchRequest BuildRequest()
        {
            SearchRequest request = new SearchRequest();

            // Common request fields (required)
            request.AppId = AppId;
            request.Query = "microsoft offices";
            request.Sources = new SourceType[] { SourceType.Phonebook };

            // Common request fields (optional)
            request.Version = "2.0";
            request.Market = "en-us";
            request.UILanguage = "en";
            request.Latitude = 47.603450;
            request.LatitudeSpecified = true;
            request.Longitude = -122.329696;
            request.LongitudeSpecified = true;
            request.Radius = 10.0;
            request.RadiusSpecified = true;
            request.Options = new SearchOption[] { SearchOption.EnableHighlighting };

            // Phonebook-specific request fields (optional)
            request.Phonebook = new PhonebookRequest();
            request.Phonebook.Count = 10;
            request.Phonebook.CountSpecified = true;
            request.Phonebook.Offset = 0;
            request.Phonebook.OffsetSpecified = true;
            request.Phonebook.FileType = "YP";
            request.Phonebook.SortBy = PhonebookSortOption.Distance;
            request.Phonebook.SortBySpecified = true;

            return request;
        }

        static void DisplayErrors(XmlNode errorDetails)
        {
            // Add the default namespace to the namespace manager.
            XmlNamespaceManager nsmgr = new XmlNamespaceManager(errorDetails.OwnerDocument.NameTable); nsmgr.AddNamespace("api", "http://schemas.microsoft.com/LiveSearch/2008/03/Search");

            XmlNodeList errors = errorDetails.SelectNodes("./api:Errors/api:Error", nsmgr);

            if (errors != null)
            {
                // Iterate over the list of errors and display error details.
                Console.WriteLine("Errors:");
                Console.WriteLine();
                foreach (XmlNode error in errors)
                {
                    foreach (XmlNode detail in error.ChildNodes)
                    {
                        Console.WriteLine(detail.Name + ": " + detail.InnerText);
                    }

                    Console.WriteLine();
                }
            }
        }
    }
}

　　代码中使用的AppId需要去Bing Developer Center申请（免费），上面的AppId是我在测试代码的时候申请的，应该可以使用。接下来我们需要在工程中创建两个Web Page来测试这两个类，下面是这两个页面的测试代码（HTML & C#）：

WebSourceType.aspx

<h2>
    Using the Web SourceType Over the SOAP Protocol</h2>
This example shows how to perform the following tasks:
<ul>
    <li>Set search request basic parameters by using the <a href="http://msdn.microsoft.com/en-us/library/dd250960.aspx"
        target="_blank">SearchRequest</a> type.</li>
    <li>Set the Web book request by using the <a href="http://msdn.microsoft.com/en-us/library/dd250886.aspx"
        target="_blank">WebRequest</a> type. </li>
    <li>Display the results obtained from the <a href="http://msdn.microsoft.com/en-us/library/dd250843.aspx"
        target="_blank">SearchResponse</a> type. </li>
</ul>
<h4>
    See Also
</h4>
<span style="background-color: Yellow"><a href="http://msdn.microsoft.com/en-us/library/dd251056.aspx"
    target="_blank">BING API</a></span>
<br />
<br />
<span style="background-color: Yellow">For more information, see <a href="http://blogs.msdn.com/morebits/"
    target="_blank">Technical Notes</a></span>
<br />
<br />
<asp:Table ID="WebResultID" BorderWidth="1" runat="server">
    <asp:TableHeaderRow BackColor="LightGray">
        <asp:TableCell ID="hdrID1" BorderStyle="Inset" />
    </asp:TableHeaderRow>
</asp:Table>

WebSourceType.aspx.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using BingSearchDemo.net.live.search.api;

namespace BingSearchDemo
{
    public partial class WebSourceType : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        // Get the search results. Display one result per row.
        private void DisplayResults(SearchResponse response)
        {
            int j = 0;
            foreach (WebResult result in response.Web.Results)
            {
                TableRow tRow = new TableRow();
                WebResultID.Rows.Add(tRow);
                TableCell tCell = new TableCell();
                tCell.BorderWidth = Unit.Parse("1");
                if (j % 2 == 0)
                    tCell.BackColor = System.Drawing.Color.Blue;
                else
                    tCell.BackColor = System.Drawing.Color.Tomato;
                tCell.ForeColor = System.Drawing.Color.Yellow;
                tCell.Font.Bold = true;
                System.Text.StringBuilder builder = new System.Text.StringBuilder();
                builder.AppendLine(result.Title);
                builder.AppendLine(result.Description);
                builder.AppendLine(result.Url);
                builder.Append("Last Crawled: ");
                builder.AppendLine(result.DateTime);
                j++;
                int i = 0;
                foreach (char c in builder.ToString().ToCharArray())
                {
                    if (c == '\uE000')
                    {
                        // If the current character is the begin highlighting
                        // character (U+E000), change it to a left square bracket.
                        builder[i] = Convert.ToChar('[');
                    }
                    else if (c == '\uE001')
                    {
                        // If the current character is the end highlighting
                        // character (U+E001), change it to a right square bracket.
                        builder[i] = Convert.ToChar(']');
                    }
                    i++;
                }
                tCell.Text = builder.ToString();
                tRow.Cells.Add(tCell);
            }
        }

        protected override void OnPreRender(EventArgs e)
        {
            base.OnPreRender(e);
            SearchResponse response = UsingWebSourceType.PerformLiveSearch();
            string results = string.Format("Displaying {0} to {1} of {2} results", response.Web.Offset + 1,
                           response.Web.Offset + response.Web.Results.Length, response.Web.Total);
            // Add header information to the table.
            hdrID1.Text = "<div style='color:red; font-weight:bold'>Bing API Version: " + response.Version + "</div>" +
                            "<div style='color:red; font-weight:bold'>Web results for " + response.Query.SearchTerms + "</div>" +
                            "<div style='color:red; font-weight:bold'>" + results + "</div>";
            // Add rows to the table that contain search results.
            DisplayResults(response);
        }
    }
}

PhonebookSourceType.aspx

PhonebookSourceType.aspx.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using BingSearchDemo.net.live.search.api;

namespace BingSearchDemo
{
    public partial class PhonebookSourceType : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        // Get the search results. Display one result per row.
        private void DisplayResults(SearchResponse response)
        {
            int j = 0;
            foreach (PhonebookResult result in response.Phonebook.Results)
            {
                TableRow tRow = new TableRow();
                WebResultID.Rows.Add(tRow);
                TableCell tCell = new TableCell();
                tCell.BorderWidth = Unit.Parse("1");
                if (j % 2 == 0)
                    tCell.BackColor = System.Drawing.Color.Blue;
                else
                    tCell.BackColor = System.Drawing.Color.Tomato;
                tCell.ForeColor = System.Drawing.Color.Yellow;
                tCell.Font.Bold = true;
                System.Text.StringBuilder builder = new System.Text.StringBuilder();
                builder.AppendLine(result.Business);
                builder.AppendLine(result.Address);
                builder.Append(result.City);
                builder.Append(", ");
                builder.AppendLine(result.StateOrProvince);
                builder.AppendLine(result.PhoneNumber);
                builder.Append("Average Rating: ");
                builder.AppendLine(result.UserRating.ToString());

                j++;
                int i = 0;
                foreach (char c in builder.ToString().ToCharArray())
                {
                    if (c == '\uE000')
                    {
                        // If the current character is the begin highlighting
                        // character (U+E000), change it to a left square bracket.
                        builder[i] = Convert.ToChar('[');
                    }
                    else if (c == '\uE001')
                    {
                        // If the current character is the end highlighting
                        // character (U+E001), change it to a right square bracket.
                        builder[i] = Convert.ToChar(']');
                    }
                    i++;
                }
                tCell.Text = builder.ToString();
                tRow.Cells.Add(tCell);
            }
        }

        protected override void OnPreRender(EventArgs e)
        {
            base.OnPreRender(e);
            SearchResponse response = UsingPhonebookSourceType.PerformLiveSearch();
            string results = string.Format("Displaying {0} to {1} of {2} results", response.Phonebook.Offset + 1,
                           response.Phonebook.Offset + response.Phonebook.Results.Length, response.Phonebook.Total);
            // Add header information to the table.
            hdrID1.Text = "<div style='color:red; font-weight:bold'>Bing API Version: " + response.Version + "</div>" +
                            "<div style='color:red; font-weight:bold'>Phonebook results for " + response.Query.SearchTerms + "</div>" +
                            "<div style='color:red; font-weight:bold'>" + results + "</div>";
            // Add rows to the table that contain search results.
            DisplayResults(response);
        }
    }
}

　　下面是在我机器上使用上面两种类型执行查询的结果：

　　Bing Search Service API的详细介绍和SDK文档可以去Bing Developer Center，本文给出的例子在这里下载。

原文地址