How to send data to an external Web site to query and return the results of an external Web site query

How to send data to an external Web site to query and return the results of an external Web site query
For example Express http://www.kuaidi100.com/This website, it can be the user in this website to enter the courier number sent to The courier company's website for inquiries, and The courier company website query results returned to the site.

This is generally through what technology to achieve Ah, is the AJAX technology, or PHP in the Curl technology, I think it is very magical, because it does not need to query the verification code is not required input. Is there any great God who can elaborate on the principle, or give me a sample source program, please?
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I think it should be an API call, thank you.
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Take a look at the API section for yourself.
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If the API is not available on other sites
Only use curl to crawl, and then use the regular match to the content you need it
Now that you're using curl, there's no need to convert to JSON.

It is best to grab the necessary resources to their own server to save, and then call, if the dynamic to crawl a lot of time

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