Javascript: Using a string as a variable name in the code

Question

I am writing JavaScript code that has a loop. There is statement in the loop: foo = foo +1. ; I want the code to treat foo as different variable each time the loop runs. For example:

first loop -->  env.x = env.x + 2.0 ;
second loop --> env.y = env.y+ 2.0 ;
third loop -->  env.z = env.z + 2.0 ;

I have looked at other solutions posted like using eval() and window() functions but still can't figure how to do this.

UPDATE: To help better understand my problem I am posting a part of the code:

if (profile.xChaos.toFixed(0) > 500.) {
                               
if (profile.param1 == 2.0) { 
profile.param1 = 0.25 ;
profile.param2 += 0.25 ;
console.log('Reset. param1 =' + profile.param1 + '; param2 increment = '+profile.param2);
}
else{profile.param1 += 0.25 ;}
profile.gui.updateDisplay({verbose : false}) ;
}

I would like to implement this in such a way that the code effectively executes these lines as:

if (profile.xChaos.toFixed(0) > 500.) {
                               
if (profile.x == 2.0) { 
profile.x = 0.25 ;
profile.y += 0.25 ;
console.log('Reset. x =' + profile.x + '; y increment = '+profile.y);
}
else{profile.x += 0.25 ;}
profile.gui.updateDisplay({verbose : false}) ;
}

where x,y can be chosen from a set of variables {profile.a, profile.b, profile.c . . .}. I hope this makes it clearer. Thanks.

Use an object instead, don't use variables. – VLAZ Sep 30 '20 at 23:05 — VLAZ, Sep 30 '20 at 23:05

score 2 · Accepted Answer · answered Sep 30 '20 at 23:05

2

Make an array of property names, then iterate over that:

const keys = ['x', 'y', 'z'];
for (const key of keys) {
  env[key] = env[key] + 2.0;
}

answered Sep 30 '20 at 23:05

CertainPerformance

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Thanks for the solution. However, I have a complicated piece of code inside the "for". I am looking for a solution where I can use a small variable name like var1 and var2 an then just set var1 and var2 that act as env.x or env.y or env.z as required. – oodNinja Oct 01 '20 at 01:55
Generally, when you have a question, you should post your *actual code*, not psuedo-code - that way you can receive useful answers. Can you post your actual code? – CertainPerformance Oct 01 '20 at 02:10
To be clear, post some actual code, but usually a minimal reproduction of the issue you have. – dwjohnston Oct 01 '20 at 02:53
I used the method given by @CertainPerformance and it worked flawlessly. Marking the problem as solved. Thank you all. – oodNinja Oct 02 '20 at 10:38

Javascript: Using a string as a variable name in the code

1 Answers1