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JavaScript

Posted by Jackie Jen
Jackie Jen
2,723 Points

how to combine variable in javascript

let said i want the javascript variable of 'var ru' and the symbol u is a number that keep increasing. therefore i do not want to manually insert var ru;

but in javascript i wrote the code var ("r" + "u")=100; document.getElementById("demo").innerHTML =ru;

but did not show any thing

Roman Kuzhelev
Roman Kuzhelev
7,853 Points

Kenny,

regarding the specific case you've mentioned (and not a problem of dynamic variable's name generation) - why would not consider just to use an array instead?

3 Answers

Michael Hulet
Michael Hulet
47,913 Points
Michael Hulet
Michael Hulet
47,913 Points

This StackOverflow thread gives you a few good ways to do this

romanok
romanok
4,556 Points
romanok
romanok
4,556 Points

Not sure if that's what you mean, but anyway:

if you want to combine 2 number variables into a string, you can use .toString() method.

So if you have

var r = 10

and

var u = 0

you can do:

var ru = r.toString() + u.toString()

ru will be '100'

There's also .parseInt() method to convert strings to numbers

Stone Preston
Stone Preston
42,016 Points

i think what hes after is a way to dynamically generate a variable name maybe?. some languages let you do that sort of thing. dont know if its possible in javascript.

Jackie Jen
Jackie Jen
2,723 Points

If let said I would like to have var r1 var r2 var r3 var r4 var r5

But i dun want manually write those 5 variable. i would like to use for loop for (y=1; y<6; y++){ var ("r"+y); }

am i doing the right things?

Tech Solutions
Tech Solutions
6,077 Points
Tech Solutions
Tech Solutions
6,077 Points

so you want the variable r to remain static but the variable u to be dynamic?

var r = 1;
var u = function u(){
    for(var i = 0; i > 5; i++;)
});
var ru = r + u;