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Nejc Vukovic
Full Stack JavaScript Techdegree Graduate 51,574 PointsReferencing variables and their values
Hi there to all.
I came to a point where I would need some ideas or maybe info on the matter of variable referencing.
I have 2 arrays of strings and I want to bind two index values together -> I want to change a value from Array A with a variable of Array B. The trick is that I don't want to overwrite the value.
A solution could be Array C where I save the relation between the two but I don't want to litter the back end with endless arrays.
Does anybody have an idea how to go about it?
1 Answer
Karolin Rafalski
11,368 PointsOne thing to consider is that array values are passed by reference... if you change a value in a or c, it changes for both of them:
var a = [1,2,3,4];
var b = a
a[0]=888;
b[3]=777;
console.log(a);
//[ 888, 2, 3, 777 ]
console.log (b);
//[ 888, 2, 3, 777 ]
If you need to create a new array based on one of these arrays it is best to use .map, .forEach or a for loop to build a new array.
Alternatively, it actually seems like what you might want to use is a constructor function and create new instances of an object that stores the values you want, as you need them? https://css-tricks.com/understanding-javascript-constructors/
miikis
44,957 Pointsmiikis
44,957 PointsHey Nejc,
Can you post some code? I'm not sure what you mean by "binding" the index values. Or why Array A contains "values" and Array B contains "variables." If you would provide some example code, it would go a long way towards illustrating the particular problem you're facing and thus it would make it much easier for forum participants to understand and help you out.