I am new to Amazon marketplace web service (MWS). I have read documentation of web service but I am unable to understand which api suit for update quantity and price of single or multiple product at one time.
Here is link that I am reading so far and don't know where to start.(http://docs.developer.amazonservices.com/en_US/feeds/Feeds_SubmitFeed.html)
Can you guys suggest me where to start?
Check out the feed types. You're going to want to submit a pricing or inventory feed to update your inventory. Once you have a feed created, you submit that using the SubmitFeed operation.
For an overview on how feeds works, check out this What you should know about the Amazon MWS Feeds API section.
Specifically for ASP.NET, there is an SDK built that will help you greatly. If you want to know how to implement that as a web api, that's another topic, but you can wrap code from the SDK inside a web api endpoint. But start with understanding MWS.
