Jquery how to assign the name of variable (dynamically)

Question

To assign a value to a variable is very simple just do it this way

var foo = "bar";

But to assign a name to the variable (dynamically) as you have to do?

var variableName = "newName";
var variableName = "bar";    // in this case assign new value of variableName

Do I have to do it this way?

var foo + "_" + variableName = "foo"  // foo_newName = "bar"

i don think this is possible in javascript...you are trying to create variable name dynamically ...how is that possible it not about javascript it not possible in c# also as per my knowldege — Pranay Rana, Jul 27 '15 at 07:23
You can only have dynamic properties of objects (including the global object, `window`, if you like), but not local variables. — GregL, Jul 27 '15 at 07:24
variables are nothing but identifiers and they store some value, and any mathematical operation you intend are going to be performed on the values. I can't think what exactly you are trying to solve? creating dynamic variables and accessing them conditionally is native to any programming language including gw-basic : ) — Manish Mishra, Jul 27 '15 at 07:24
it is possible only if your variables are global or under some scope. — iamawebgeek, Jul 27 '15 at 07:25
possible duplicate of http://stackoverflow.com/questions/22727711/javascript-dynamic-variable-names — Anand, Jul 27 '15 at 07:29
[Look this answer please : Use dynamic variable names in JavaScript][1] [1]: http://stackoverflow.com/questions/5117127/use-dynamic-variable-names-in-javascript — devseo, Jul 27 '15 at 07:29

score 10 · Accepted Answer · answered Jul 27 '15 at 07:28

10

You can make dynamic variable using this way

window['varname'] = "test";

alert(varname);

answered Jul 27 '15 at 07:28

Romnick Susa

Thanks is what I was looking for – Gus Jul 27 '15 at 07:29
No problem, Please accept the answer if it worked to you. Happy coding. – Romnick Susa Jul 27 '15 at 07:32

score 4 · Answer 2 · answered Jul 27 '15 at 07:28

4

You can do that by using eval(), but there are some Reservations about using that method:

eval("foo_" + i + "='bar'")

answered Jul 27 '15 at 07:28

Tariq

What reservations would those be? – ThickMiddleManager Jan 10 '20 at 19:30
1

Hii This function is used in different languages but Using it (specifically) with javascript on client side (browser) is not that bad. Here is a link about eval function: https://stackoverflow.com/questions/197769/when-is-javascripts-eval-not-evil# – Tariq Jan 12 '20 at 08:31

score 2 · Answer 3 · answered Jul 27 '15 at 07:30

As per my understanding, you can not create variables like this, however, you can use object and set its property.

var foo = "bar";
var variableName = "newName";

window[foo + "_" + variableName]  = "foo" ;
console.log(bar_newName);

or

var foo = "bar";
var variableName = "newName";

var obj = {};

obj[foo + "_" + variableName]  = "foo" ;
console.log(obj["bar_newName"]);

3 Answers3