The Bing Search API provides a very flexible set of methods to submit queries and retrieve results from the Bing Engine. In this article I will show how you can use this API from delphi.
Getting Started
Before to start read the terms of use of the Bing API which states “…The API is intended to deliver relevant results (collectively, “Bing results”) for queries submitted to Microsoft’s Bing service and other related Microsoft services (collectively, “Bing services”) for rendering within a customer-facing or end-user-facing website (“Website”) or application“..(So it’s ok use this API from a desktop application)
To use the Bing API you must get an Application ID from the Bing Developer Center and include this AppId in the API calls.
You can send a request to the Bing Search API and get the response in one of these protocols JSON (JavaScript Object Notation), XML (Extended Markup Language) or SOAP (Simple Object Access Protocol).
The protocol is identified in the used URI, check these samples URLs
JSON http://api.bing.net/json.aspx?AppId= YOUR_APPID &Version=2.2&Market=en-US&Query=testign&Sources=web+spell&Web.Count=1
XML http://api.bing.net/xml.aspx?AppId= YOUR_APPID &Version=2.2&Market=en-US&Query=testign&Sources=web+spell&Web.Count=1
SOAP http://api.bing.net/search.wsdl?AppID=YourAppId&Version=2.2
Before to choose the appropriate response protocol you must evaluate the kind of application which are you developing, in this article I choose the XML protocol due that can be implemented im most of the delphi versions without use third party libraries (Note : the only limitation using the XML response is which the length of the requested URL is limited by the maximum URL length.)
Building the URL
When you uses the Bing XML interface, you must make a HTTP GET using a URL like this
http://api.bing.net/xml.aspx?AppId= YOUR_APPID &Version=2.2&Market=en-US&Query=testign&Sources=web+spell&Web.Count=1&xmltype=elementbased
Appid : is the Application ID
Version : Version of the API to use (recommended is 2.2)
Market : prefered language of the search results
Query : the sentence to search
Web.Count : the number of results to get
xmltype : this field control control the flavor of XML interface. If ElementBased enumeration is specified, each field will be rendered as a separated tag. If AttributeBased enumeration is specified, all simple type fields will be rendered as attributes instead of elements. The default value is ElementBased.
Sources : indicate the types of data to retrieve (see Working with SourceTypes) (you can use multiple values in this files separated by an +)
the values of this field can be
Image (Bing, Version 2.0)
News (Bing, Version 2.0)
Phonebook (Bing, Version 2.0)
RelatedSearch(Bing, Version 2.0)
Spell(Bing, Version 2.0)
Translation (Bing, Version 2.2)
Video (Bing, Version 2.x)
Web (Bing, Version 2)
Depending of how you construct your URL the XML returned can vary (see Using XML (Bing, Version2) for a sample output XML).
The code
After of build the URL you must make a GET request to access the Bing API. you can use your favorite component like WinInet, Indy and so on. In my case I choose the IXMLHTTPRequest interface to make GET request because I can use the same object to parse the XML result.
Check the next snippets using the AttributeBased and elementbased values in the xmltype field and how the parse procedure changes depending of this value.
And calling any of these methods in this way
Will produce this output
As you probably note , the above source code only parses the result when the response includes a web search result, so now we are to expand this code to support and parse any result returned by the Bing API (Web search, Images, Videos, etc.)
Check the next full sample