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：

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); 
                    } 
                } 
            } 
        } 
    } 
}

 

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#）： 

<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>

  

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); 
        } 
    } 
}

  

<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>

  

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