Nodejs writes a JSON file and formats the output JSON method

Let’s say I need to serialize data as a JSON string and write it to a data.json file:

1 let str = JSON.stringify(data)
2 
3 fs.writeFile('data.json',str,function(err){
4 if (err) {res.status(500).send('Server is error...')}
5 })
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When you put it in a JSON file, you get a really nasty line, look at that

Can’t stand it right!!

Vanilla JS’s json.stringify () made the output beautiful and intuitive.

The first piece of code can be written like this, with the third argument set to “\t” (the second argument must be filled, which can be written as “” or null) :

let str = JSON.stringify(data,"","\t")

let str = JSON.stringify(data,null,"\t")
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Then data.json can do this