const regex = /K'(?P<name1>81|61|64|44|86|678|41|49|33|685|1(?:33|45)?|\d{2,3})\d+/g;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('K\'(?P<name1>81|61|64|44|86|678|41|49|33|685|1(?:33|45)?|\\d{2,3})\\d+', 'g')
const str = `K'8134567
K'81345678
K'6134516789
K'61345678
K'643456
K'646345678
K'1234567890
K'12345678901
K'1454567890 <<<--- want 145 returned and not 1
K'13345678901 <<<--- want 133 returned and not 1
K'3214567890123
K'32134567890123
K'3654567890123
K'8934567890123
K'6554567890123
I am interested in the digits after K'
I am looking to do this using regex but not sure if it can be done. What I want is:
if the number starts with 81 return 81
if the number starts with 61 return 61
...
if the number starts with something i am not interested in return other(or its first digits of 1-3)
The above criteria works:
but what I also want is:
if the fist digit is 1 then return 1 BUT
if the fist digit is 1 and the 2nd and 3rd digit are 45 return 145 and don't return just 1
if the fist digit is 1 and the 2nd and 3rd digit are 33 return 133 and don't return just 1
I presume I have to put something inside this part of the regex |(1)\\d+|
Questions:
Does regex sort the data first?
Is the order of the regex search important to how it is implemented? i deally I do not want this.
`;
// Reset `lastIndex` if this regex is defined globally
// regex.lastIndex = 0;
let m;
while ((m = regex.exec(str)) !== null) {
// This is necessary to avoid infinite loops with zero-width matches
if (m.index === regex.lastIndex) {
regex.lastIndex++;
}
// The result can be accessed through the `m`-variable.
m.forEach((match, groupIndex) => {
console.log(`Found match, group ${groupIndex}: ${match}`);
});
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions