Script / Code to check an output of a webpage and return result

I am looking for a script e.g. perl or code - C# etc. in order to che开发者_如何学Cck a webpage for a string.

For example to check if a php page is running, we can echo Hello World, and the script would then check for the string "Hello World" on the webpage output and return true or false.

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Fetch the data with LWP, then run a pattern match over the retrieved document.

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Look for a ScreenScraper in your preferred language. You can use it to get the HTML output of the site and get a specific part, like paragraphs, images or - like in your case - a single string (mostly using XPath).