How to delete the element which matches filter within the list in object of JSON-CodePudding

Sorry for my French and stupid question, but i need to DELETE some elements in JSON file while I don't now anything in JSON and JS

There is the structure: `

{ "questions": [
    {
        "id": 1,
        "quizId": 1,
        "question": "Какому автомобилю разрешается остановка в зоне действия этих знаков?",
        "correctAnswer": 4,
        "image": "1.jpg",
        "answers": [
            "Красному.",
            "Обоим автомобилям.",
            "Ни одному.",
            "Ни одному.",
            "Желтому, обозначенному опознавательным знаком \"Инвалид\".",
            "-"
        ]
    },
    {
        "id": 2,
        "quizId": 1,
        "question": "По каким направлениям из числа обозначенных стрелками разрешается движение?",
        "correctAnswer": 4,
        "image": "2.jpg",
        "answers": [
            "Только по направлению А.",
            "Только по направлению Б.",
            "Только по направлению В.",
            "-",
            "-",
            "-."
        ]
    } 
]
}

And I need to find the elements within answers array which equals to "-" and delete it.

So output should be:

{ "questions": [
    {
        "id": 1,
        "quizId": 1,
        "question": "Какому автомобилю разрешается остановка в зоне действия этих знаков?",
        "correctAnswer": 4,
        "image": "1.jpg",
        "answers": [
            "Красному.",
            "Обоим автомобилям.",
            "Ни одному.",
            "Ни одному.",
            "Желтому, обозначенному опознавательным знаком \"Инвалид\".",
        ]
    },
    {
        "id": 2,
        "quizId": 1,
        "question": "По каким направлениям из числа обозначенных стрелками разрешается движение?",
        "correctAnswer": 4,
        "image": "2.jpg",
        "answers": [
            "Только по направлению А.",
            "Только по направлению Б.",
            "Только по направлению В."
        ]
    } 
]
}

I tried to solve the problem, but unsuccessfully. Thanks for your answers!

CodePudding user response：

To accomplish this task, you could use some server-side scripting, I recommend NodeJS as it is directly related to JS.

You can see the documentation here: https://nodejs.dev/en/

Within the NodeJS project, you will have to use the File System module https://nodejs.org/api/fs.html

Having the above configured, the code would be as follows:

import fs from "fs"
const file_path = “YOUR_JSON_FILE_PATH”

let json_file_content = JSON.parse(fs.readFileSync(file_path).toString());

  for (let i in json_file_content.questions) {
    json_file_content.questions[i].answers = 
    json_file_content.questions[i].answers.
    filter(answer => (answer != "-" && answer != "-."))
  }
 
fs.writeFileSync(file_path, JSON.stringify(json_file_content));

The above code can be described as follows:

The FileSystem module is imported
A constant is created which contains the path where your .json file is located
We create a variable “json_file_content” which will contain the content of your .json file

To get this content, do the following:

Get the content of your file using readFileSync
This content is converted to string type using toString
Subsequently, it is converted to JSON using JSON.parse

Having the json in a variable, simple JS code can now be applied, Inside that code what is happening is this:

All questions contained in the object are iterated
For each question, their answers are accessed
The answers are filtered, eliminating those that are equal to "-" and "-."

Finally:

The filtered json is converted to a string
The new string (JSON) is written into your file using writeFileSync