How to get Keywords used from a Search Engine

I am using C# asp.NET and I have searched the internet up and down trying to find a solution to this problem. In google analytics they have the keywords used by search engine开发者_开发技巧s so there must be a way to do it. thanks

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Do you mean determining the search keywords that led a user to your site? This is done by analyzing the referrer URL.

string referrer = Request.UrlReferrer.ToString();

Most of them are pretty simple, but there are different patterns for different search engines.

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I found out that besides implementing your own algorithm to extract keywords I can use google analytics to do this. Google has an api for their analytics software and this is what i have been using. The only thing that is difficult is if you have more then 10,000 pages you have to open an adwords account.