Exploring ways to loop through values within nested objects

Question

Exploring ways to loop through values within nested objects

const schoolArr = {
  class10: { 
           studentInfo: {name: 'John'}, 
           exam: {result: 'pass'} 
           },
  class11: { 
           studentInfo: {name: 'Alis'}, 
           exam: {result: 'pass'} 
           },
  class12: { 
           studentInfo: {name: 'Nick'}, 
           exam: {result: 'fail'} 
           }
};

Looking for a solution to generate a list of student names if the exam result is 'pass'. The classes (class10, class11, class12) are dynamically changing and I'm struggling with how to iterate through these dynamic values.

The desired output should be an array like this: student = ['John', 'Alis']

javascript typescript

Answer 1

Answer №1

Here is the solution for restructuring the updated object:

First, filter out the object values.
Next, map to extract the names of students.

Keep in mind: It is possible to destructure objects at multiple levels.

Another important point: Avoid using the same key multiple times in an object as it will overwrite the previous entry with that key, which can lead to unexpected behavior.

const schoolArr = {
  class10: {
    studentInfo: { name: 'John' },
    exam: { result: 'pass' }
  },
  class11: {
    studentInfo: { name: 'Alis' },
    exam: { result: 'pass' }
  },
  class12: {
    studentInfo: { name: 'Nick' },
    exam: { result: 'fail' }
  }
};

console.log(
  Object.values(schoolArr)
    .filter(({ exam: { result } }) => result === 'pass')
    .map(({ studentInfo: { name } }) => name)
);

Answer 2

Here is the solution for restructuring the updated object:

First, filter out the object values.
Next, map to extract the names of students.

Keep in mind: It is possible to destructure objects at multiple levels.

Another important point: Avoid using the same key multiple times in an object as it will overwrite the previous entry with that key, which can lead to unexpected behavior.

const schoolArr = {
  class10: {
    studentInfo: { name: 'John' },
    exam: { result: 'pass' }
  },
  class11: {
    studentInfo: { name: 'Alis' },
    exam: { result: 'pass' }
  },
  class12: {
    studentInfo: { name: 'Nick' },
    exam: { result: 'fail' }
  }
};

console.log(
  Object.values(schoolArr)
    .filter(({ exam: { result } }) => result === 'pass')
    .map(({ studentInfo: { name } }) => name)
);

Exploring ways to loop through values within nested objects

Answer №1

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