If value is not a plain array, such code will work fine:

var value = { "aaa": "111", "bbb": "222", "ccc": "333" };
var blkstr = [];
$.each(value, function(idx2,val2) {                    
  var str = idx2 + ":" + val2;
  blkstr.push(str);
});
console.log(blkstr.join(", "));
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>

(output will appear in the dev console)

As Felix mentioned, each() is just iterating the array, nothing more.

Answer from user447356 on Stack Overflow
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W3Schools
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tabnine.com โ€บ home โ€บ array to string in javascript
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geeksforgeeks.org โ€บ javascript โ€บ convert-array-to-string-in-javascript
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medium.com โ€บ konsole-blog โ€บ 5-ways-to-convert-array-to-string-in-javascript-f6a92ac5788f
5 ways to convert Array to String in Javascript | by David Petrosyan | Konsole.blog | Medium
May 23, 2022 - We check to see if the element is equal to 'b'. If it is, we append that element with a separator. Otherwise we append the element without the separator. You can also use the array.reduce() method for joining with custom logic. The previous example with a for loop can be rewritten like this: const myArray = ['a', 'b', 'c', 'c', 'b', 'a', 'd']const myString = myArray.reduce((stringAccumulator, currentElement) => { const separator = ';' if (currentElement === 'b') { return stringAccumulator += (currentElement + separator) } return stringAccumulator += currentElement }, '')console.log(myString) // 'ab;ccb;ad'
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w3schools.com โ€บ js โ€บ js_arrays.asp
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geeksforgeeks.org โ€บ javascript โ€บ javascript-array-tostring-method
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masteringjs.io โ€บ tutorials โ€บ fundamentals โ€บ array-tostring
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medium.com โ€บ @louistrinh โ€บ converting-arrays-to-strings-in-javascript-4d1bbea80c20
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