Get multiple regex match result all in one match by Javascript-CodePudding

I am trying to make my code looks professional by removing those duplicate code. the question is I want to get some data from a string, to be specific, I need to know the NUMBER, X, Y, Z, A, B, etc. values but the regex expression are different for each variable so I have to repeat myself writing a lot of duplicate code.

let TextString = `DRILL(NUMBER:=20,NAME:='4',PN:=1,X:=10.1,Y:=73.344,Z:=0,A:=-1.435,B:=1.045,M1:=1,M2:=2,M3:=3,M4:=4,M5:=1,S1:=10.5,S2:=2.1,S3:=1.2,S4:=2,S5:=2.4,RS1:=1,RS2:=2);`;
const regNumber = /(?<=NUMBER:=)[0-9] /gm;
let lineNumber = Number(TextString.match(regNumber));

const regX = /(?<=X:=)(-?[0-9] )(.[0-9] )?/gm;
let X = Number(TextString.match(regX)).toFixed(1);

const regY = /(?<=Y:=)(-?[0-9] )(.[0-9] )?/gm;
let Y = Number(TextString.match(regY)).toFixed(1);

const regZ = /(?<=Z:=)(-?[0-9] )(.[0-9] )?/gm;
let Z = Number(TextString.match(regZ)).toFixed(1);

const regA = /(?<=A:=)(-?[0-9] )(.[0-9] )?/gm;
let A = Number(TextString.match(regA)).toFixed(1);

const regB = /(?<=B:=)(-?[0-9] )(.[0-9] )?/gm;
let B = Number(TextString.match(regB)).toFixed(1);
// and many more duplicate code.

console.log(lineNumber, X, Y, Z, A, B);

I could only think of a way like the above, to match each variable individually and run .match() multiple times, but as you can see there are 17 variables total and in real situations, there are hundreds of these TextString. I was worried that this matching process will have a huge impact on performance.

Are there any other ways to fetch all variables in one match and store them in an array or object? or any other elegant way of doing this?

CodePudding user response：

Every coordinate will have a single letter identifier, so you can use a more general positive lookback (?<=,[A-Z]:=). This lookback matches a comma followed by a single uppercase letter then the equality symbol.

You can then use .match() to get all matches and use .map() to run the conversion you were doing.

let TextString = `DRILL(NUMBER:=20,NAME:='4',PN:=1,X:=10.1,Y:=73.344,Z:=0,A:=-1.435,B:=1.045,M1:=1,M2:=2,M3:=3,M4:=4,M5:=1,S1:=10.5,S2:=2.1,S3:=1.2,S4:=2,S5:=2.4,RS1:=1,RS2:=2);`;
const regNumber = /(?<=NUMBER:=)[0-9] /gm;
let lineNumber = Number(TextString.match(regNumber));

const regex = /(?<=,[A-Z]:=)(-?[0-9] )(.[0-9] )?/gm;
let coord = TextString.match(regex).map(n => Number(n).toFixed(1));

console.log(lineNumber, coord);

CodePudding user response：

Every value match a pattern :=[value], or :=[value]) for the last one. So there is my regex

(?<=:=)-?[\d\w.'] (?=[,)])

Positive Lookbehind (?<=:=) look for match behind :=
-? match - optional (for negative number)
[\d\w.'] : match digit, word character, ., '
Positive Lookahead (?=[,)]) look for match ahead character , or )

Live regex101.com demo

Now change your code to

 let TextString = `DRILL(NUMBER:=20,NAME:='4',PN:=1,X:=10.1,Y:=73.344,Z:=0,A:=-1.435,B:=1.045,M1:=1,M2:=2,M3:=3,M4:=4,M5:=1,S1:=10.5,S2:=2.1,S3:=1.2,S4:=2,S5:=2.4,RS1:=1,RS2:=2);`;
 const regexPattern= /(?<=:=)-?[\d\w.'] (?=[,)])/g;
 console.log(TextString.match(regexPattern))
 // ['20', "'4'", '1', '10.1', '73.344', '0', '-1.435', '1.045', '1', '2', '3', '4', '1', '10.5', '2.1', '1.2', '2', '2.4', '1', '2']