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JavaScript Express Basics Parameters, Query Strings, and Modularizing Routes Card Template

Ceil-Ian Maralit
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Ceil-Ian Maralit
Front End Web Development Techdegree Graduate 19,434 Points
Posted by Ceil-Ian Maralit
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Ceil-Ian Maralit
Front End Web Development Techdegree Graduate 19,434 Points

Where did the req.query came from?

Can someone please explain to me where did all of those came from? Cause I can't seem to get it. Are those terms just made by him?

Also, how did he just use [id][side] without selecting if what he wants is a question or an answer from the json file? I mean, he did not even travel through the object like for example, cards.question or cards.answer, something like that. Can someone please help?

Thank you in advance!

1 Answer

Marco Cornejo
Marco Cornejo
3,411 Points
Marco Cornejo
Marco Cornejo
3,411 Points

req is an object, that has a query property. Basically, IF AND ONLY IF your request has a query, it is stored in it (the query property), otherwise NOTHING is stored. And, since the JSON file has the "question" and "answer" as properties of "card", we may perform a query search.

Basically, what the instructor is doing is that, IF AND ONLY IF his URL is: http://localhost:3000/cards/1?side=answer

His code will know that req.query has a Key:Value of side:answer. Answer will be stored in const "side", and the required card and side will be displayed accordingly.

He isn't selecting a question or an answer because he doesn't need to, the user (or a button, or a search) will write that url with the query(key,value) such as '?side=question', but for now he is manually typing the entire URL, which you can watch him doing so in the last few seconds of the video.

I hope I was clear enough.