How do I convert an array of objects to an array including only one property's values?-CodePudding

I am trying to use the .includes( ) array method to check if an item is in my JSON file. So far I have made a connection to the database (using JSON server npm plugin) and have retrieved the array of objects back, and stored them in the variable "fetchedData". Now, I know that .includes( ) takes an array as the first argument and searches within the array for the second argument. How do I convert this array of objects to an array including just the name property values? Is this how .includes( ) works?

This is the JSON file:

  "savedexercises": [
    {
      "name": "all fours squad stretch",
      "target": "quads",
      "gifUrl": "http://d205bpvrqc9yn1.cloudfront.net/1512.gif",
      "id": 1
    },
    {
      "name": "ankle circles",
      "target": "calves",
      "gifUrl": "http://d205bpvrqc9yn1.cloudfront.net/1368.gif",
      "id": 2
    },
    {
      "name": "arm slingers hanging bent knee legs",
      "target": "abs",
      "gifUrl": "http://d205bpvrqc9yn1.cloudfront.net/2355.gif",
      "id": 3
    }
  ]
}

I am just trying to access all the name property values and then store them into an array.

CodePudding user response：

You can you filter and map to find all the values of a particular key and transform it to an array of objects or any form. Includes will only tell you if such a key exists. Refer the code below

  const createArraybasedOnkey= (key) => {
    console.log(
      obj.savedexercises
        .filter((x) => x[key])
        ?.map((x) => {
          return { [key]: x[key] };
        })
    );
  };

code sandbox : https://codesandbox.io/s/pedantic-rain-u1t9th?file=/src/App.js:625-817

CodePudding user response：

Use array.map(). For example:

const exerciseNames = savedexercises.map(exercise => exercise.name)
// Expected output:
// ["all fours squad stretch", "ankle circles",
//  "arm slingers hanging bent knee legs"]

// Now you can check if the exerciseNames includes a certain exercise:
console.log(exerciseNames.includes("all fours squad stretch"))
// Expected output: true