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关于javascript:使用clarinetbrowsernodejs解析重复key值的json字符串

简略粗犷, 间接上代码,
会把 {"a":1,"a":2} 解析成 {"a":[1,2]}
附上 npm 链接:clarinet

var clarinet = require("clarinet");

class InvalidJSON {result = {}
    /**
     * @description 进入的括号层数
     */
    bracketCount = 0
    /**
     * @type {Array<{ type: 'array'; value: any[] } | {type: 'object'; arrayKeys: string[]; arrayKeysMap: {[key: string]: boolean; }; keys: string[]; value: { [key: string]: any } }> }
     */
    queue = []
    
    get lastQueue() {
        const queue = this.queue
        return queue[queue.length - 1]
    }
    
    queuePop() {this.queue.pop()
        this.bracketCount--
    }
    
    queuePush(item) {this.queue.push(item)
        this.bracketCount++
    }
    
    onopenobject(key) {// console.log('onopenobject', key)
        const value = {}
        this.bracketCount === 0 && (this.result = value)
        this.lastQueue && this.onvalue(value)
        this.queuePush({keys: [key], arrayKeys: [], arrayKeysMap: {}, type: 'object', value })
    }
    
    onkey(key) {// console.log('onkey', key)
        const {keys, type, arrayKeys} = this.lastQueue
        if (type !== 'object') {return}
        keys.includes(key) && arrayKeys.push(key)
        keys.push(key)
    }
    
    onvalue(v) {// console.log('onvalue', v)
        const {type, value, keys, arrayKeysMap, arrayKeys} = this.lastQueue
        if (type === 'array') {value.push(v)
        } else if (type === 'object') {const lastKeys = keys[keys.length - 1]
            if (arrayKeys.includes(lastKeys)) {if (!arrayKeysMap[lastKeys]) {arrayKeysMap[lastKeys] = true
                    value[lastKeys] = [value[lastKeys]]
                }
                value[lastKeys].push(v)
            } else {value[lastKeys] = v
            }
        }
    }
    
    oncloseobject() {// console.log('onclosearray')
        this.queuePop()}
    
    onopenarray() {// console.log('onopenarray')
        const value = []
        this.bracketCount === 0 && (result = value)
        this.lastQueue && this.onvalue(value)
        this.queuePush({type: 'array', value})
    }
    
    onclosearray() {// console.log('onclosearray')
        this.queuePop()}

    /**
     * @param {string} json 不非法的 json
     */
    parse(json) {
        this.bracketCount = 0
        this.result = {}
        this.queue = []
        this.parser.write(json).close()
        return this.result
    }
    
    parser

    constructor() {const parser = clarinet.parser()
        const parserEvents = ['value', 'openobject', 'key', 'closeobject', 'openarray', 'closearray']
        parserEvents.forEach(event => {const eventName = `on${event}`
            parser[eventName] = (...args) => this[eventName](...args)
        })
        this.parser = parser
    }
}

const invalidJSON = new InvalidJSON()

console.log(JSON.stringify(invalidJSON.parse('{"p":7,"p": 9,"w":3,"q":[0,8],"g":77,"g":{"a":100,"d":{"z":2},"d":{"z":3}}}')))

原理:clarinet 会解析 json 字符串, 在每个 json 字符串关键点触发回调,
如开始一个 object, 进入一个 key, 进入一个 value, 开始一个 array,
利用这些回调, 拼装出冀望的格局

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