I have a sanitizeStr() function that I need to run on EVERY property/subproperty that exists in an object like the one below:

const data = {
  info: 'schools',
  schools: [
    { name: 'Johnson Elementary', type: 'elementary' },
    { name: 'Iselin Middle School', type: 'middle' }
  ],
  bestStudent: {
    name: 'John',
    grade: 'sixth'
  }
};

The issue is that for every single one of these properties, they may or may not exist. Right now, I'm having to do multiple if checks for each property and manually running the function:

// Is there a better way to do this rather than what I have here:

if (data.info) {
  data.info = sanitizeStr(data.info);
}

if (data.bestStudent) {
  if (data.bestStudent.name) {
    data.bestStudent.name = sanitizeStr(data.bestStudent.name);
  }

  if (data.bestStudent.grade) {
    data.bestStudent.grade = sanitizeStr(data.bestStudent.grade);
  }
}

if (data.schools) {
  data.schools.forEach((school, i) => {
    if (school.name) {
      data.schools[i].name = sanitizeStr(school.name);
    }

    if (school.grade) {
      data.schools[i].grade = sanitizeStr(school.grade);
    }
  });
}

If anyone knows of a cleaner/less manual way of doing this, it would be appreciated.

I have a sanitizeStr() function that I need to run on EVERY property/subproperty that exists in an object like the one below:

const data = {
  info: 'schools',
  schools: [
    { name: 'Johnson Elementary', type: 'elementary' },
    { name: 'Iselin Middle School', type: 'middle' }
  ],
  bestStudent: {
    name: 'John',
    grade: 'sixth'
  }
};

The issue is that for every single one of these properties, they may or may not exist. Right now, I'm having to do multiple if checks for each property and manually running the function:

// Is there a better way to do this rather than what I have here:

if (data.info) {
  data.info = sanitizeStr(data.info);
}

if (data.bestStudent) {
  if (data.bestStudent.name) {
    data.bestStudent.name = sanitizeStr(data.bestStudent.name);
  }

  if (data.bestStudent.grade) {
    data.bestStudent.grade = sanitizeStr(data.bestStudent.grade);
  }
}

if (data.schools) {
  data.schools.forEach((school, i) => {
    if (school.name) {
      data.schools[i].name = sanitizeStr(school.name);
    }

    if (school.grade) {
      data.schools[i].grade = sanitizeStr(school.grade);
    }
  });
}

If anyone knows of a cleaner/less manual way of doing this, it would be appreciated.

• javascript
• string
• sanitization

• what is sanitizeStr doing? please add the function as well. – Nina Scholz Commented Mar 27, 2017 at 21:21
• I didn't include it because I don't think it's quite relevant – It just does some string replacements. I'm basically just trying to figure out a better way to run that function on every property without having to do it one by one manually. – Saad Commented Mar 27, 2017 at 21:23
• Possible duplicate of Iterate through object properties – Heretic Monkey Commented Mar 27, 2017 at 21:23
• @MikeMcCaughan I'm aware of how to iterate through an object's properties. However, I can't just do a loop and run sanitizeStr on each prop in the loop because the property might be a string, an object, or an array of objects. – Saad Commented Mar 27, 2017 at 21:24
• And you can't check the type before running sanitizeStr on a property? typeof stringVar === 'string'... – Heretic Monkey Commented Mar 27, 2017 at 21:27

2 Answers 2

You could use an iterative and recursive approach for objects and call the function for non objects only.

function sanitizeStr(s) {
    return '#' + s;
}

function iterAll(object) {
    Object.keys(object).forEach(function (k) {
        if (object[k] && typeof object[k] === 'object') {
            iterAll(object[k]);
            return;
        }
        object[k] = sanitizeStr(object[k]);
    })
}

var data = { info: 'schools', schools: [{ name: 'Johnson Elementary', type: 'elementary' }, { name: 'Iselin Middle School', type: 'middle' }], bestStudent: { name: 'John', grade: 'sixth' } };

iterAll(data);

console.log(data);

.as-console-wrapper { max-height: 100% !important; top: 0; }

You must me looking for this

const sanitizeObject = (obj, callBack, isClone = false) => {
    let tempObj = obj;
    if(typeof callBack === 'function' && (typeof tempObj === 'string' || typeof tempObj === 'number')){
      return callBack(tempObj)
    }else if(typeof tempObj === 'object' && tempObj !== null){
      tempObj = isClone ? (Array.isArray(tempObj) ? [...tempObj] : {...tempObj}) : tempObj;
      Object.keys(tempObj).forEach(objKey => {
        const valueOfobject = tempObj[objKey]
        if(typeof valueOfobject === 'string' || typeof valueOfobject === 'number'){
          tempObj[objKey] = callBack(tempObj[objKey])
        }else {
          tempObj[objKey] = sanitizeObject(valueOfobject, callBack, isClone)
        }
      })
    } 
    return tempObj;
}

const data = {
test1: {
  test2: [{
  property: "any string",
  property2: null
}]}
}

console.log(sanitizeObject(data, function (stringValue){
  return stringValue + " apend"
}))