John Cooper - 21 days ago 9

Javascript Question

What does radix actually means? Why do we need it?

`parseInt(10, radixValue);`

Answer Source

You might not always want to parse the integer into a base 10 number, so supplying the radix allows you to specify other number systems.

The radix is the number of values for a single digit. Hexidecimal would be 16. Octal would be 8, Binary would be 2, and so on...

In the `parseInt()`

function, there are several things you can do to hint at the radix without supplying it. These can also work against you if the user is entering a string that matches one of the rules but doesn't expressly mean to. For example:

```
// Numbers with a leading 0 used a radix of 8 (octal) before ECMAScript 5.
// These days, browsers will treat '0101' as decimal.
var result = parseInt('0101');
// Numbers that start with 0x use a radix of 16 (hexidecimal)
var result = parseInt('0x0101');
// Numbers starting with anything else assumes a radix of 10
var result = parseInt('101');
// Or you can specify the radix, in this case 2 (binary)
var result = parseInt('0101', 2);
```