How to convert an hex string to a Hex number

[chirs]

Hi,

I'd like to use a var to hold a Hex number. But in this code:

var a = "ffff00"

a is a string. var a=ffff00 will not work either. How can I put a
Hex number ffff00 into a var?

Thanks

Chris

 

[Lasse Reichstein Nielsen]

I'd like to use a var to hold a Hex number. But in this code:

var a = "ffff00"

a is a string. var a=ffff00 will not work either. How can I put a
Hex number ffff00 into a var?

var a = 0xffff00;

In Javascript, and most other languages with a C like syntax,
hexadecimal numbers are written with a prefix "0x".

 

[Douglas Crockford]

I'd like to use a var to hold a Hex number. But in this code:

var a = "ffff00"

a is a string. var a=ffff00 will not work either. How can I put a
Hex number ffff00 into a var?

Buy a book. You can't program in total ignorance. I recommend Flanagan's
Definitive Guide (4th Ed) from O'Reilly.

Try

var a = 0xffff00;

http://www.crockford.com/javascript/javascript.html

 

[Dr John Stockton]

JRS: In article <[email protected]>, seen

I'd like to use a var to hold a Hex number.

Variables hold IEEE Doubles as the only form of number, except maybe in
future. You can, however, use Hex notation to specify the contents of a
variable.

But in this code:

var a = "ffff00"

a is a string. var a=ffff00 will not work either. How can I put a
Hex number ffff00 into a var?

var a = 0xffff00 // 1. to give a literal in Hex

var HS = "ffff00"

var a = +("0x"+HS) // 2. using existing string

var a = parseInt(HS, 16) // 3. normal, using existing string

Here 2 & 3 give different result with different illegal strings HS; try
"fated" & "defeat"; I prefer the former.