为什么我没有从 eBay 获得产品价格的响应？

Question

I get ebay product information this way:

http://open.api.ebay.com/shopping?
   callname=FindProducts&
   responseencoding=XML&
   appid=YourAppIDHere&
   siteid=0&
   version=525&
   QueryKeywords=harry%20potter&
   AvailableItemsOnly=true&
   MaxEntries=2

But I don't get product price in responce. Should I shange the request parameters? Or may be I should use another method of ebay Web services to get this information?

The response is

<FindProductsResponse xmlns="urn:ebay:apis:eBLBaseComponents">
<Timestamp>2012-11-30T06:54:54.713Z</Timestamp>
<Ack>Success</Ack>
<Build>E799_CORE_BUNDLED_15523174_R1</Build>
<Version>799</Version>
<ApproximatePages>700</ApproximatePages>
<MoreResults>true</MoreResults>
<PageNumber>1</PageNumber>
<Product>
<DomainName>DVDs</DomainName>
<DetailsURL>
http://syicatalogs.ebay.com/ws/eBayISAPI.dll?PageSyiProductDetails&IncludeAttributes=1&ShowAttributesTable=1&ProductMementoString=119128:2:1049:4276619924:441341764:7a3b4632d7a0c4ee860c374349c61b36:1:1:1:5000000672733
</DetailsURL>
<DisplayStockPhotos>true</DisplayStockPhotos>
<ProductID type="Reference">110258144</ProductID>
<ProductID type="UPC">883929182879</ProductID>
<ItemSpecifics>
<NameValueList>
<Name>Movie Rating</Name>
<Value>PG-13 (MPAA)</Value>
</NameValueList>
<NameValueList>
<Name>Genre</Name>
<Value>Childrens</Value>
</NameValueList>
<NameValueList>
<Name>Format</Name>
<Value>DVD</Value>
</NameValueList>
<NameValueList>
<Name>Work Name</Name>
<Value>Harry Potter: Complete 8-Film Collection</Value>
</NameValueList>
<NameValueList>
<Name>Region Code</Name>
<Value>Region 1</Value>
</NameValueList>
</ItemSpecifics>
<ReviewCount>195</ReviewCount>
<StockPhotoURL>
http://i.ebayimg.com/00/$(KGrHqV,!g0E6ZCwQ)wpBOuWbUNB,g~~_6.JPG?set_id=89040003C1
</StockPhotoURL>
<Title>
Harry Potter: Complete 8-Film Collection (DVD, 2011, 8-Disc Set)
</Title>
</Product>
<Product>
<DomainName>DVDs</DomainName>
<DetailsURL>
http://syicatalogs.ebay.com/ws/eBayISAPI.dll?PageSyiProductDetails&IncludeAttributes=1&ShowAttributesTable=1&ProductMementoString=119128:2:1049:1597262630:429151180:bf834db05cfb5150fe073087ebe92117:1:1:1:1415162318
</DetailsURL>
<DisplayStockPhotos>true</DisplayStockPhotos>
<ProductID type="Reference">99846530</ProductID>
<ProductID type="UPC">883929139446</ProductID>
<ItemSpecifics>
<NameValueList>
<Name>Movie Rating</Name>
<Value>PG-13 (MPAA)</Value>
</NameValueList>
<NameValueList>
<Name>Genre</Name>
<Value>Science-Fiction/Fantasy</Value>
</NameValueList>
<NameValueList>
<Name>Director</Name>
<Value>David Yates</Value>
</NameValueList>
<NameValueList>
<Name>Format</Name>
<Value>DVD</Value>
</NameValueList>
<NameValueList>
<Name>Work Name</Name>
<Value>Harry Potter and the Deathly Hallows: Part I</Value>
</NameValueList>
<NameValueList>
<Name>Region Code</Name>
<Value>Region 1</Value>
</NameValueList>
<NameValueList>
<Name>Producer</Name>
<Value>David Heyman</Value>
</NameValueList>
</ItemSpecifics>
<ReviewCount>163</ReviewCount>
<StockPhotoURL>
http://i.ebayimg.com/00/$(KGrHqF,!l0E2DwP)(v!BNo16imfYQ~~_6.JPG?set_id=89040003C1
</StockPhotoURL>
<Title>
Harry Potter and the Death

Answer 1

Check this Link : Getting Item Descriptions and Item Specifics http://developer.ebay.com/DevZone/shopping/docs/CallRef/GetSingleItem.html#sampledescriptionitemspecifics

URL format (HTTP GET). See also the non-wrapped version of this URL. For results in a format other than XML, specify a different value for responseencoding.

http://open.api.ebay.com/shopping?
   callname=GetSingleItem&
   responseencoding=XML&
   appid=YourAppIDHere&
   siteid=0&
   version=515&
   ItemID=180126682091&
   IncludeSelector=Description,ItemSpecifics

You have to pass ItemID to get Detailed Description .

Answer 2

Going by this info it seems like certain values have a conditional occurrence in the response. So maybe you may need to check if price is firstly returned or not by the response and if not, query another api with say the product id value. HTH.