正则 纳税号,GST标识号（GSTIN）的正则表达式

What is the regex for the GST number in India. You can read more about the GST numbers from https://cleartax.in/s/know-your-gstin

On a summary level the number is represented as

List itemThe first two digits of this number will represent the state code as per Indian Census 2011

The next ten digits will be the PAN number of the taxpayer

The thirteenth digit will be assigned based on the number of registration within a state

The fourteenth digit will be Z by default

The last digit will be for check code

解决方案

Here is the regex and checksum validation for GSTIN

\d{2}[A-Z]{5}\d{4}[A-Z]{1}[A-Z\d]{1}[Z]{1}[A-Z\d]{1}

Format details

First 2 digits of the GST Number will represent State Code as per the Census (2011).

Next 10 digits will be same as in the PAN number of the taxpayer.

First five will be alphabets

Next four will be numbers

Last will be check code

The 13th digit will be the number of registration you take within a state i.e. after 9, A to Z is considered as 10 to 35 .

14th digit will be Z by default.

Last would be the check code.

Here is the code for verifying/validating the gstin number using the checksum in js

function checksum(g){

let a=65,b=55,c=36;

return Array[‘from’](g).reduce((i,j,k,g)=>{

p=(p=(j.charCodeAt(0)c?1+(p-c):p;

return k<14?i+p:j==((c=(c-(i%c)))<10?c:String.fromCharCode(c+b));

},0);

}

console.log(checksum(’27AAPFU0939F1ZV’))

console.log(checksum(’27AASCS2460H1Z0′))

console.log(checksum(’29AAGCB7383J1Z4′))