Preparing number using abbreviations

RegEx for BMHT in a sequence is my previous post. I'开发者_Python百科m looking to build a number using abbreviations, and ofcourse using regex.

Now I know how to validate a number with BMTH abbreviations.

Now my next and final target is to build a number using the abbreviations. e.g. -2T2H22.55 should be displayed as -2,222.55 -2M2H22.63 should be displayed as -2,000,222.63

Help appreciated.

Flex's scripting language, ActionScript, is an ECMAScript implementation like JavaScript, so regex literals have to be delimited with slashes, for example: /^(?:\d+B)?(?:\d{1,3}M)?(?:\d{1,3}T)?(?:\d{1}H)?(\.[0-9]*)?/.

But that regex still has some problems. For one thing, you don't account for the minus sign or the two digits after the hundreds place. And, while the decimal point may be optional, if it is present you should require it to be followed by at least one digit (so +, not * in that last group).

Finally, you'll need to capture the various components so you can use them to construct the number. Here's my result:

/^(-?)(?:(\d+)B)?(?:(\d{1,3})M)?(?:(\d{1,3})T)?(?:(\d)H)?(\d{0,2})(\.\d+)?$/

The minus sign, if present, will be captured in group $1. The rest of the components will be in groups $2 through $7. You can use them in a callback function to construct the number. Also, notice that everything in this regex is optional; it will match an empty string or just a hyphen, so you'll need to check for that.