In JS, t, = ＞ Analysis of

data:

var t = [{
    
					nodeCode: '59',
					nodeName: ' International Primary School ',
					children: [{
    
						nodeCode: '37',
						nodeName: 'PYP Primary school ',
						children: [{
    
								nodeCode: '99',
								nodeName: ' second grade ',
								children: null,
								billOpened: null,
							},
							{
    
								nodeCode: '100',
								nodeName: ' Third grade ',
								children: null,
								billOpened: true,
							},
							{
    
								nodeCode: '101',
								nodeName: ' Fourth grade ',
								children: null,
								billOpened: true,
							},
							{
    
								nodeCode: '102',
								nodeName: ' Fifth grade ',
								children: [{
    
									nodeCode: '1011',
									nodeName: ' Class one ',
									children: null,
									billOpened: true,
								}, ],
								billOpened: true,
							},
						],
						billOpened: true,
					}, ],
					billOpened: true,
				},
				{
    
					nodeCode: '59',
					nodeName: ' International Primary School ',
					children: [{
    
						nodeCode: '37',
						nodeName: 'PYP Primary school ',
						children: [{
    
								nodeCode: '99',
								nodeName: ' second grade ',
								children: null,
								billOpened: null,
							},
							{
    
								nodeCode: '100',
								nodeName: ' Third grade ',
								children: null,
								billOpened: true,
							},
							{
    
								nodeCode: '101',
								nodeName: ' Fourth grade ',
								children: null,
								billOpened: true,
							},
							{
    
								nodeCode: '102',
								nodeName: ' Fifth grade ',
								children: [{
    
									nodeCode: '1011',
									nodeName: ' Class one ',
									children: null,
									billOpened: true,
								}, ],
								billOpened: true,
							},
						],
						billOpened: true,
					}, ],
					billOpened: true,
				},
			];

const recUpdate = (t, f) =>({
     ...t, children: t?.children?.map(c => recUpdate(c, f)), ...f(t) })
const formatBillOpened = t =>recUpdate(t, _ => ({
     billOpened: false }))
formatBillOpened(t)
console.log(t)

recUpdate(t, _ => ({ billOpened: false })) It's an arrow function. I'm confused , Why use this _ As a function parameter ？ Later, I checked the information , not have understood until then , Under normal circumstances , If we write an arrow function that does not require parameters , This is how it is written

recUpdate= () => {/ Code /}

1
If we use () How to write it , This arrow function will not pass arguments , If the underline is used as a parameter

recUpdate(t, _ => ( {/ Code /}）

2
After a search , Confirmed that this is a reference golang Variable Underlined ideas

In a nutshell , This is this. recUpdate Function can have a parameter , Just use _ To express , But internally executed code does not call parameters , That is, no interest in parameters . It can also be understood as , This variable must be filled in when using the arrow function , But I don't want to use , I'm too lazy to name , Avoid making information noise .

（） and _ These two ways of writing , The same functions are realized , But now I prefer to use _, because _ And （） comparison , Occupy fewer pixels , There is a better way , Ignore the meaning of this variable ！

Global modification t Array billOpened by false

let loop = (t) => {
    
    t.map(item => {
    
		item.billOpened = false
		item.children && loop(item.children)
    })
}
loop(t)
console.log(t)

let strT=JSON.stringify(t).replace(/\s+/g,"");
let result=strT.replaceAll("\"billOpened\":true", "\"billOpened\":false")
console.log(JSON.parse(result))