Is it possible to create a variable based on the value of more than one variable?

Question

For example A = 10, i want to create a variable with the value in it.

Like this: var i10 or if A = 2, i wanna create a variable like this var i2.

For e.g. A = 10 and B = 5, i want a var A10B5, is that possible?

Edit: more information

Possible duplicate of http://stackoverflow.com/questions/5117127/javascript-dynamic-variable-name — Gerald Schneider, Aug 02 '13 at 07:55
Have a look here - http://stackoverflow.com/questions/5117127/javascript-dynamic-variable-name — Mark Walters, Aug 02 '13 at 07:55
@GeraldSchneider you beat me by two seconds with the same reference — Mark Walters, Aug 02 '13 at 07:56
nonono what if i have more than one variables that i want in my varible? For e.g. A = 10 and B = 5, i want a var A10B5, is that possible? — abcd1234123123, Aug 02 '13 at 07:57
There is (almost) *never* a reason to create variables dynamically. What problem are you trying to solve with this? — Felix Kling, Aug 02 '13 at 08:14
im doing a calendar and i need to create a variable for all the dates on the calendar. i figured that this would be a good way to do it. — abcd1234123123, Aug 02 '13 at 08:17
Use a twodimensional array. `Dates[A][B] = 'value'`. It will save you a lot of redundant code. — Gerald Schneider, Aug 02 '13 at 08:20

score 3 · Accepted Answer · edited May 23 '17 at 11:50

It is possible, as explained in detail in this question on SO.

A = 10;
B = 5;

window['A' + A + 'B' + B] = 'Hello';

alert(A10B5);
// alerts: Hello

See a demo in this jsfiddle.

I don't see the point of it though though, since you have to keep a reference of the name of this object it's easier to store the value in a local variable inside a function or object that has always the same name or use an array to store the value.

Proposed solution for the intended use:

Use a two-dimensional array:

Calendar[A][B] = 'value';

By creating dynamic variables you will have to rebuild the name of the variable every time you need to access it it. By using a two-dimensional array you can just use the array with both variables, that spares you the code to rebuild the variable name over and over again and makes it easier to read and maintain.

score 1 · Answer 2 · answered Aug 02 '13 at 08:07

var A = 10, B = 5;
window['A' + A + 'B' + B] = "You should avoid polluting global " + 
                            "scope at all costs.";
alert(A10B5);

Instead you should resort to objects:

var myVars = {}, A = 10, B = 5;
myVars['A' + A + 'B' + B] = "Just like this.";
alert(myVars.A10B5);

score 1 · Answer 3 · answered Aug 02 '13 at 08:12

1

You can create dynamic variables with eval() function

var a = 10;
eval("variable" + a + " = a");

this return a variable with name "variable10" and value "10".

Take a look here too!

For more information: w3schools eval()

Hope it helps ^_^

answered Aug 02 '13 at 08:12

Alesanco

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Ouch. `eval()` should be used very very carefully and avoided if possible. – Gerald Schneider Aug 02 '13 at 08:13
However, many people suggest it as a solution to create variable names dynamically.. – Alesanco Aug 02 '13 at 08:21

score 0 · Answer 4 · answered Aug 02 '13 at 07:55

0

You can have A = 10 and B = A which takes the same amount in a different variable, however, you also can make an if statement like

if(A > 10){ A = 11 }

answered Aug 02 '13 at 07:55

no name

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score 0 · Answer 5 · edited May 23 '17 at 12:28

0

check this out

`a = 'varname';

str = a+' = '+'123';

eval(str);

alert(varname); `

edited May 23 '17 at 12:28

Community

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answered Aug 02 '13 at 08:16

Ankit Tyagi

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You provide a link to a good solution and accompany it with an example of a completely different, unrelated (and possibly dangerous) example? – Gerald Schneider Aug 02 '13 at 08:18

Is it possible to create a variable based on the value of more than one variable?

5 Answers5