更改 JavaScript 对象键的大小写

Question

I have following object.

var obj = [{
  Address1: "dd",
  Address2: "qww",
  BankAccNo: "44",
  BankBranchCode: "44",
  BloodGrp: "A+"
},
{
  Address1: "dd",
  Address2: "qww",
  BankAccNo: "44",
  BankBranchCode: "44",
  BloodGrp: "A+"
}];

How can I make all of the keys uppercase?

I want to be able to access values like this : - obj[0].ADDRESS1

Answer 1

obj = obj.map( function( item ){
    for(var key in item){
        var upper = key.toUpperCase();
        // check if it already wasn't uppercase
        if( upper !== key ){ 
            item[ upper ] = item[key];
            delete item[key];
        }
    }
    return item;
});

http://jsfiddle.net/07xortqy/

Answer 2

1. Loop over all the properties in the object (with for in )
2. Use .toUpperCase() to get the uppercase version of the property name
3. Copy the value from the original property to the uppercase version
4. delete the original property

Answer 3

For anyone looking for a solution working with objects, arrays, and nested objects or arrays:

 // rename function depending on your needs const capitalizeKeys = (obj) => { const isObject = o => Object.prototype.toString.apply(o) === '[object Object]' const isArray = o => Object.prototype.toString.apply(o) === '[object Array]' let transformedObj = isArray(obj) ? [] : {} for (let key in obj) { // replace the following with any transform function const transformedKey = key.replace(/^\\w/, (c, _) => c.toUpperCase()) if (isObject(obj[key]) || isArray(obj[key])) { transformedObj[transformedKey] = capitalizeKeys(obj[key]) } else { transformedObj[transformedKey] = obj[key] } } return transformedObj } const t = { test1: 'hello', test2: { aa: 0, bb: '1', cc: [ 3, '4', 'world'] }, test3: [{ aa: 5, bb: '6' }, { cc: [ 'hello', 'world', 7 ] } ] } console.log(JSON.stringify(capitalizeKeys(t)))

(this function is to be adapted since I only had to capitalize the first letter, and there is no need for the helper functions to be nested)

Answer 4

$.each(obj, function(i, parent) {
  $.each(parent, function(key, record) {
    parent[ key.toUpperCase() ] = record[key]; //rename key
    delete parent[key]; //delete old key
  });
});

Answer 5

let obj = [
{ Address1: "dd",Address2: 'qww',BankAccNo: 44,BankBranchCode: 44,BloodGrp: 'A+' },
{ Address1: "dd",Address2: 'qww',BankAccNo: 44,BankBranchCode: 44,BloodGrp: 'A+' }
];

const uppercaseKeys = (elem) => {
  let newObject = {}

  Object.keys(elem).reduce( (acc, key, allKeys) => {
    acc[key.toUpperCase()] = elem[key]
    delete elem[key]
    return acc
  }, elem)

  return newObject
}

obj.forEach( o => uppercaseKeys )
console.log(obj)

Answer 6

You can now also use Object.fromEntries() in combination with Object.entries() - have a look at the Object transformations section.

const obj2 = obj1.map(item => Object.fromEntries(Object.entries(item).map(([key, val]) => [
  key.toUpperCase(),
  val
])));

I've detailed the steps below:

// Iterate through each item in array
const obj2 = obj1.map(item => {
  // Object.entries() method returns array of object's own enumerable string-keyed property [key, value] pairs, 
  // in the same order as that provided by a for...in loop
  const entries = Object.entries(item);

  // Convert keys to uppercase
  const uppercaseEntries = entries.map(([key, val]) => [
    key.toUpperCase(),
    val
  ]);

  // Object.fromEntries() method transforms a list of key-value pairs into an object.
  return Object.fromEntries(uppercaseEntries);
});`

https://jsfiddle.net/buj5y32x/3/

Answer 7

For wider support, you are better off using Object.keys() with Array.reduce() .

const obj2 = obj1.map(item =>
  Object.keys(item).reduce((accumulator, key) => {
    // accumulator is the new object we are creating
    accumulator[key.toUpperCase()] = item[key];
    return accumulator;
  }, {})
);

https://jsfiddle.net/qf81ezsy/

Answer 8

You could just loop through them and add new entries?

for (index in obj) {
  for (key in obj[index]) { 
     obj[index][key.toUpperCase()] = obj[key]; 
  }
}