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Conditional statement inside for(var key in object) Javascript

I have a json data with specific key as below:

var object = {"85":{"id":"50","nosurat":"2020-PKL-001","user_created":"02211"},"69":{"id":"50","nosurat":"2020-PKL-002","user_created":"02212"},"104":{"id":"50","nosurat":"2020-PKL-003","user_created":"02213"}};

So, in order to iterate it, I use for method. The problem is how to make filters inside the for method, but only execute it once?

for(var keys in object){
   if(object[keys].nosurat == "2020-PKL-001"){

In the above code, the functionx() executed 3 times, because once it’s true, it will loop through as many key as my object has. How to make functionx() only executed once in a while, only when the condition is met, assuming that there will be another key that met the condition.


or you could use Array.prototype.some():

var obj = {"85":{"id":"50","nosurat":"2020-PKL-002","user_created":"02211"},"69":{"id":"50","nosurat":"2020-PKL-001","user_created":"02212"},"104":{"id":"50","nosurat":"2020-PKL-001","user_created":"02213"}};
function functionx(o){console.log(o)}
console.log('=== correct behaviour ========================');
Object.values(obj).some(o=>o.nosurat=="2020-PKL-001" && functionx(o) || true);
console.log('=== alternative correct version ==============');
Object.values(obj).some(o=>o.nosurat=="2020-PKL-001" && (functionx(o),true) );
console.log('===== WRONG behaviour (previous version ======');
Object.values(obj).some(o=>o.nosurat=="2020-PKL-001" && functionx(o));
.as-console-wrapper {max-height:100% !important}

Oooops, I just corrected a tiny detail: I forgot to mention that in my original solution functionx(o) needed to return some “truthy” value, otherwise multiple calls would still have happened in some()!

I changed the relevant part of the code now to (functionx(o) || true). This will make sure that some() will definitely stop after the first functionx() call (regardless of whatever functionx might return).

One further remark on the && within the function of the .some() loop: the evaluation of boolean expressions follows strict “lazy” rules in JavaScript (as in almost every other language): terms are evaluated from left to right only as far as necessary to get the result of the whole expression. So if the term before the && evaluates as false the overall result of the expression is determined and nothing after the && could change it anymore. Therefore functionx will not be called in these situations and false will be returned to the calling .some() loop.