JavaScript Get letters in between other letters

Question

Hello.. I kinda need help using REGEX I never understood it , I tried multiple times.. But everytime I run into something requiring REGEX my mind just goes blank.. I have some integers in an array and some text behind them.. for example M:44, 45C:65, 66 I want to get everything after M: that's before C: then get everything after C: the numbers are actually char codes so I made them integers

Answer 1

If I right understand, you have an array like:

var data = [ "M:44", "45C:65", "66" ];

... where all items are string?
Or are your data of another type? Number, Object? or even a mix?

Give us more description about your data representation if you want to be accuratly helped... even share your actual code using it ;)

Answer 2

/*
Ok, you have a string such as "M:44, 45C:65, 66", and you want to extract "44, 45"?

As you have always the pattern "M:"+value2extract+"C:"+secondValue and never have more than once time 'M' and only once "C", you can avoid use of regular expression:
*/

var data = "M:44, 45C:65, 66";
var i = data.indexOf('C');
var extract = data.substring(2,i); // data to be extracted start always at 3rd character (index: 2) and end at index of 'C'

console.log(extract); // "44, 45"

// Else, using regex:

var re = /^M:([^C]*)C:/;
// first '^' mark start of string,
// () surround the part to be captured,
// [^C] define a class of all characters excluding 'C'
// * search for 0 or any previous element (any times any character appart 'C')

extract = re.exec(data)[1];
// returned object by RegEcp.exec() method is an array-like
// index 0 contains string matching rexgex
// next indexes contains value of captured parenthesis groups (here only once, at index 1)

console.log(extract); // "44, 45"

Answer 3

If you're interested by encoding/decoding variables in text format, you should look at JSON object: it allow you to stringify() and parse() saving time of handling it by yourself (and more efficiently ^^)...

What I would do would be:
> store my data in objects instead in a string directly:
var data = {M:[], C:[]}; // create an empty model
data.M.push(44); // populate inner array
data.M.push(45);
data['C'].push(65);
data['C'].push(66);
> when need to export to string:
var datastr = JSON.stringify(data); // '{"M":[44,45],"C":[65,66]}'
> when need to import string:
var decoded = JSON.parse(datastr);
> now you can use the decoded object as the initial 'data' object:
var listM = decoded.M; // [44,45]
> wich is already an array with integer values (if you have pushed integer initially, obviously ;P):
var sum = listM[0]+listM[1]; // 89

Answer 4

https://code.sololearn.com/W1M716ZzPOzA/?ref=app

Answer 5

I convert the message and amount of clicks to an array of char codes eventually I want to read it as data from a code in that format

Answer 6

I'm still so confused lmao but I will practice from the use of your first example once I get the hang of it , write a function for it and convert it to an integer to be placed into one of the variables , also what do you think about the idea of the game? I used something like it before, so thought I'd recreate it , you have to click the egg to unlock the message

Answer 7

That seems like a much better way to go about things lol , Thank you! I Been trying to increase my skills in JavaScript too