Develop Reference

How to join the string either with a dot, exclamation mark, or a question mark?

I want to convert a string to the sentence case. That is, uppercase the first character in each sentence and lowercase the following characters. I managed to do this. However, after splitting the string and converting it to a sentence case, I need to join it again with a corresponding character.
Here is my code that splits the string into sentences:
const string = "my seNTencE . My sentence! my another sentence. yEt another senTence? Again my sentence .";
function splitString(str) {
str = str.split(/[.!?]/);
for(let i = 0; i < str.length; i++) {
str[i] = str[i].trim();
}
for(let i = 0; i < str.length; i++) {
str[i] = str[i].charAt(0).toUpperCase() + str[i].slice(1).toLowerCase();
}
return str;
}
console.log(splitString(string));
In the return statement, I want to return joined strings. For example, the first sentence must end with a dot, and the second must end with an exclamation mark, etc. How to implement this?

str.split eliminates the result of the regex match from the string. If you want to keep it, you can place the separator in a lookbehind like this:
str.split(/(?<=[.!?])/);
The syntax (?<= ) means the regex will find positions that are preceded by punctuation, but won't include said punctuation in the match, so the split method will leave it in.
As a side note, keep in mind that this function will ruin acronyms, proper nouns, and the word I. Forcing the first letter after a period to be a capital letter is probably fine, but you will find that this function does more harm than good.

Use a regular expression with capture groups. This regex uses the lazy ? modifier so the match will end at the first [!.?], and the global g flag to grab all matches.
const string = "my seNTencE . My sentence! my another sentence. yEt another senTence? Again my sentence ."
const rx = /(.*?)([.!?])/g
const found = []
while (m = rx.exec(string)) {
let str = m[1].trim()
str = str.charAt(0).toUpperCase() + str.slice(1).toLowerCase()
found.push(str + m[2])
}
console.log(found)

capitalize first letter of word more than 3 character Regex

I code something in React and i want to use Regex to capitalize first letter of word more than 3 letters with Regex, but I'am lost with Regex, i found lot of things but nothings works. Any advice?
Regex example but dont work
"^[a-z](?=[a-zA-Z'-]{3})|\b[a-zA-Z](?=[a-zA-Z'-]{3,}$)|['-][a-z]"

\w{4,} - this regex expression will match all words that have more than 3 letters
let str = "this is Just an long string with long and short words";
const matches = str.matchAll(/\w{4,}/g);
for(match of matches) {
str = str.substring(0, match.index) + match[0].charAt(0).toUpperCase() + match[0].slice(1) + str.substring(match.index + match[0].length);
}
console.log(str);

Here are two example. One for sentences (like AidOnline01's answer, but using String#replaceAll) and a second one when using words only.
However, when using words only, you can also check for the length instead of using a regexp.
const sentence = "This is a sentence with a few words which should be capitialized";
const word = "capitialized";
// use String#replaceAll to replace all words in a sentence
const sentenceResult = sentence.replaceAll(/\w{4,}/g, word => word[0].toUpperCase() + word.slice(1));
// use String#replace for a single word
const wordResult = word.replace(/\w{4,}/, word => word[0].toUpperCase() + word.slice(1));
console.log(sentenceResult);
console.log(wordResult);

Regex match cookie value and remove hyphens

I'm trying to extract out a group of words from a larger string/cookie that are separated by hyphens. I would like to replace the hyphens with a space and set to a variable. Javascript or jQuery.
As an example, the larger string has a name and value like this within it:
facility=34222%7CConner-Department-Store;
(notice the leading "C")
So first, I need to match()/find facility=34222%7CConner-Department-Store; with regex. Then break it down to "Conner Department Store"
var cookie = document.cookie;
var facilityValue = cookie.match( REGEX ); ??

var test = "store=874635%7Csomethingelse;facility=34222%7CConner-Department-Store;store=874635%7Csomethingelse;";
var test2 = test.replace(/^(.*)facility=([^;]+)(.*)$/, function(matchedString, match1, match2, match3){
return decodeURIComponent(match2);
});
console.log( test2 );
console.log( test2.split('|')[1].replace(/[-]/g, ' ') );

If I understood it correctly, you want to make a phrase by getting all the words between hyphens and disallowing two successive Uppercase letters in a word, so I'd prefer using Regex in that case.
This is a Regex solution, that works dynamically with any cookies in the same format and extract the wanted sentence from it:
var matches = str.match(/([A-Z][a-z]+)-?/g);
console.log(matches.map(function(m) {
return m.replace('-', '');
}).join(" "));
Demo:
var str = "facility=34222%7CConner-Department-Store;";
var matches = str.match(/([A-Z][a-z]+)-?/g);
console.log(matches.map(function(m) {
return m.replace('-', '');
}).join(" "));
Explanation:
Use this Regex (/([A-Z][a-z]+)-?/g to match the words between -.
Replace any - occurence in the matched words.
Then just join these matches array with white space.

Ok,
first, you should decode this string as follows:
var str = "facility=34222%7CConner-Department-Store;"
var decoded = decodeURIComponent(str);
// decoded = "facility=34222|Conner-Department-Store;"
Then you have multiple possibilities to split up this string.
The easiest way is to use substring()
var solution1 = decoded.substring(decoded.indexOf('|') + 1, decoded.length)
// solution1 = "Conner-Department-Store;"
solution1 = solution1.replace('-', ' ');
// solution1 = "Conner Department Store;"
As you can see, substring(arg1, arg2) returns the string, starting at index arg1 and ending at index arg2. See Full Documentation here
If you want to cut the last ; just set decoded.length - 1 as arg2 in the snippet above.
decoded.substring(decoded.indexOf('|') + 1, decoded.length - 1)
//returns "Conner-Department-Store"
or all above in just one line:
decoded.substring(decoded.indexOf('|') + 1, decoded.length - 1).replace('-', ' ')
If you want still to use a regular Expression to retrieve (perhaps more) data out of the string, you could use something similar to this snippet:
var solution2 = "";
var regEx= /([A-Za-z]*)=([0-9]*)\|(\S[^:\/?#\[\]\#\;\,']*)/;
if (regEx.test(decoded)) {
solution2 = decoded.match(regEx);
/* returns
[0:"facility=34222|Conner-Department-Store",
1:"facility",
2:"34222",
3:"Conner-Department-Store",
index:0,
input:"facility=34222|Conner-Department-Store;"
length:4] */
solution2 = solution2[3].replace('-', ' ');
// "Conner Department Store"
}
I have applied some rules for the regex to work, feel free to modify them according your needs.
facility can be any Word built with alphabetical characters lower and uppercase (no other chars) at any length
= needs to be the char =
34222 can be any number but no other characters
| needs to be the char |
Conner-Department-Store can be any characters except one of the following (reserved delimiters): :/?#[]#;,'
Hope this helps :)
edit: to find only the part
facility=34222%7CConner-Department-Store; just modify the regex to
match facility= instead of ([A-z]*)=:
/(facility)=([0-9]*)\|(\S[^:\/?#\[\]\#\;\,']*)/

You can use cookies.js, a mini framework from MDN (Mozilla Developer Network).
Simply include the cookies.js file in your application, and write:
docCookies.getItem("Connor Department Store");

JavaScript: Amend the Sentence

I am having trouble below javaScript problem.
Question:
You have been given a string s, which is supposed to be a sentence. However, someone forgot to put spaces between the different words, and for some reason they capitalized the first letter of every word. Return the sentence after making the following amendments:
Put a single space between the words.
Convert the uppercase letters to lowercase.
Example
"CodefightsIsAwesome", the output should be "codefights is awesome";
"Hello", the output should be "hello".
My current code is:
Right now, my second for-loop just manually slices the parts from the string.
How can I make this dynamic and insert "space" in front of the Capital String?

You can use String.prototype.match() with RegExp /[A-Z][^A-Z]*/g to match A-Z followed by one or more characters which are not A-Z, or character at end of string; chain Array.prototype.map() to call .toLowerCase() on matched words, .join() with parameter " " to include space character between matches at resulting string.
var str = "CodefightsIsAwesome";
var res = str.match(/[A-Z][^A-Z]*/g).map(word => word.toLowerCase()).join(" ");
console.log(res);
Alternatively, as suggested by #FissureKing, you can use String.prototype.repalce() with .trim() and .toLowerCase() chained
var str = "CodefightsIsAwesome";
var res = str.replace(/[A-Z][^A-Z]*/g, word => word + ' ').trim().toLowerCase();
console.log(res);

Rather than coding a loop, I'd do it in one line with a (reasonably) simple string replacement:
function amendTheSentence(s) {
return s.replace(/[A-Z]/g, function(m) { return " " + m.toLowerCase() })
.replace(/^ /, "");
}
console.log(amendTheSentence("CodefightsIsAwesome"));
console.log(amendTheSentence("noCapitalOnFirstWord"));
console.log(amendTheSentence("ThereIsNobodyCrazierThanI"));
That is, match any uppercase letter with the regular expression /[A-Z]/, replace the matched letter with a space plus that letter in lowercase, then remove any space that was added at the start of the string.
Further reading:
String .replace() method
Regular expressions

We can loop through once.
The below assumes the very first character should always be capitalized in our return array. If that is not true, simply remove the first if block from below.
For each character after that, we check to see if it is capitalized. If so, we add it to our return array, prefaced with a space. If not, we add it as-is into our array.
Finally, we join the array back into a string and return it.
const sentence = "CodefightsIsAwesome";
const amend = function(s) {
ret = [];
for (let i = 0; i < s.length; i++) {
const char = s[i];
if (i === 0) {
ret.push(char.toUpperCase());
} else if (char.toUpperCase() === char) {
ret.push(` ${char.toLowerCase()}`);
} else {
ret.push(char);
}
}
return ret.join('');
};
console.log(amend(sentence));

single regex to capitalize first letter and replace dot

Trying out with a regex for simple problem. My input string is
firstname.ab
And am trying to output it as,
Firstname AB
So the main aim is to capitalize the first letter of the string and replace the dot with space. So chose to write two regex to solve.
First One : To replace dot with space /\./g
Second One : To capitalize the first letter /\b\w/g
And my question is, Can we do both operation with a single regex ?
Thanks in advance !!

You can use a callback function inside the replace:
var str = 'firstname.ab';
var result = str.replace(/^([a-zA-Z])(.*)\.([^.]+)$/, function (match, grp1, grp2, grp3, offset, s) {
return grp1.toUpperCase() + grp2 + " " + grp3.toUpperCase();
});
alert(result);
The grp1, grp2 and grp3 represent the capturing groups in the callback function. grp1 is a leading letter ([a-zA-Z]). Then we capturing any number of character other than newline ((.*) - if you have linebreaks, use [\s\S]*). And then comes the literal dot \. that we do not capture since we want to replace it with a space. And lastly, the ([^.]+$) regex will match and the capture all the remaining substring containing 1 or more characters other then a literal dot till the end.
We can use capturing groups to re-build the input string this way.

var $input = $('#input'),
value = $input.val(),
value = value.split( '.' );
value[0] = value[0].charAt( 0 ).toUpperCase() + value[0].substr(1),
value[1] = value[1].toUpperCase(),
value = value.join( ' ' );
$input.val( value );
It would be much easier if you simply split the value, process the string in the array, and join them back.
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" value="first.ab" id="input">