I'm using Google Chrome's Console window to try and figure out why I'm not able to loop over an array in javascript.
I have a javascript object calledmoveResult that looks like this:
I'm trying to loop over theMoveParts in javascript like this:
for (var movePart in moveResult.MoveParts) { console.log(movePart.From);};I always getundefined instead of the actual value. However, If I try to access the first item explicitly I get what I want, like this:
console.log(moveResult.MoveParts[0].From);The result of this is"b1".
Why isn't my loop working?
I've also tried a foreach:
moveResult.MoveParts.foreach(function (movePart) { console.log(movePart.From);};
1 Answer1
I'm trying to loop over the MoveParts in javascript like this:
for (var movePart in moveResult.MoveParts) { console.log(movePart.From);};I always get undefined instead of the actual value.
Don't usefor-in to loop through arrays, that's not what it's for.for-in is for looping through object properties.This answer shows various ways to loop through arrays.
The reason yourfor-in didn't work is thatmovePart is thekey, not the actual entry, so if you were using an object (not an array!) you would have usedmoveResult.MoveParts[movePart].From.
YourforEach version only failed because:
It's
forEach, notforeach. Capitalization matters in JavaScript.You were missing the closing
)on the function call.
The answer linked above has full examples offorEach and others, but here's how yours should have looked:
moveResult.MoveParts.forEach(function (movePart) { // Capital E -----------^ console.log(movePart.From); });// ^---- closing )
1 Comment
Explore related questions
See similar questions with these tags.