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This article mainly introduces "how to use nodebestpractices in NodeJS". In daily operation, I believe many people have doubts about how to use nodebestpractices in NodeJS. The editor consulted all kinds of materials and sorted out simple and easy-to-use methods of operation. I hope it will be helpful to answer the questions of "how to use nodebestpractices in NodeJS". Next, please follow the editor to study!

Nodebestpractices code style

Callback convention

Modules should expose a callback interface that takes error as the first parameter.

Module.exports=function (dragonName,callback) {

/ / write down your module logic

Vardragon=createDragon (dragonName)

/ / Note that the first parameter is error

/ / here error is null

/ / but when an error occurs, it should be an Error

Returncallback (null,dragon)

}

Always check error in the callback function

In order to better understand why to check error in the callback function, we deliberately let the program error, the next step is to fix it.

/ / thisexampleis**BROKEN**,wewillfixitsoon:)

Varfs=require ('fs')

FunctionreadJSON (filePath,callback) {

Fs.readFile (filePath,function (err,data) {

Callback (JSON.parse (data))

})

}

ReadJSON ('. / package.json',function (err,pkg) {.}

How does nodebestpractices check?

The first problem with readJSON is that he never checks to see if anything goes wrong. Now let's improve it.

/ / thisexampleis**STILLBROKEN**,wearefixingit!

FunctionreadJSON (filePath,callback) {

Fs.readFile (filePath,function (err,data) {

/ / here we check to see if there is an error.

If (err) {

/ / pass error to callback

/ / remember: the first parameter of callback is err

Callback (err)

}

/ / if that's right, pass a null and JSON

Callback (null,JSON.parse (data))

})

}

At this point, the study on "how to use nodebestpractices in NodeJS" is over. I hope to be able to solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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