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How to capitalize each words on starting of a string and after dot(.) sign?

I made a research on google and stackoverflow, below are the codes that I achieved but this will only capitalize starting of a string. Example as belows;

var str = 'this is a text. hello world!';
str = str.replace(/^(.)/g, str[0].toUpperCase());
document.write(str);

I want the string to be This is a text. Hello world!.

I have tried to use css, text-transform: capitalize; but this will result in each word to be capitalize.

aquinas
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Amran
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  • Possible duplicate of [Convert string to sentence case in javascript](http://stackoverflow.com/questions/19089442/convert-string-to-sentence-case-in-javascript) – Fiddles Nov 18 '16 at 04:15
  • also see http://stackoverflow.com/q/37457557/405180 – Fiddles Nov 18 '16 at 04:17

2 Answers2

5

I use a function like this, that takes an optional second parameter that will convert the entire string to lowercase initially. The reason is that sometimes you have a series of Title Case Items. That You Wish to turn into a series of Title case items. That you wish to have as sentence case.

function sentenceCase(input, lowercaseBefore) {
    input = ( input === undefined || input === null ) ? '' : input;
    if (lowercaseBefore) { input = input.toLowerCase(); }
    return input.toString().replace( /(^|\. *)([a-z])/g, function(match, separator, char) {
        return separator + char.toUpperCase();
    });
}

The regex works as follows

1st Capturing Group (^|\. *)
    1st Alternative ^
        ^ asserts position at start of the string
    2nd Alternative \. *
        \. matches the character `.` literally (case sensitive)
         * matches the character ` ` literally (case sensitive)
        * Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Capturing Group ([a-z])
    Match a single character present in the list below [a-z]
    a-z a single character in the range between a (ASCII 97) and z (ASCII 122) (case sensitive)

You would implement it in your example like so:

var str = 'this is a text. hello world!';
str = sentenceCase(str);
document.write(str); // This is a text. Hello world!

Example jsfiddle

PS. in future, i find regex101 a hugely helpful tool for understanding and testing regex's

haxxxton
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  • @Amran, you're welcome, please consider marking this answer as correct so that other people can find this solution – haxxxton Nov 18 '16 at 04:25
  • How does the replace function work? Sorry but I'm confuse on that – Amran Nov 18 '16 at 08:14
  • Thanks for the details @haxxxton. One more thing, what is the use of separator & char on the function? I can just use match right? – Amran Nov 20 '16 at 21:27
  • @Amran, you are correct, because the only characters that the regex captures are the first letters of new sentences, you could just use match. The difference being the semantics of converting 't' to uppercase vs. '. t'. (i have edited my answer to include a jsfiddle using match also here: https://jsfiddle.net/wue9ykxr/) However, for the minuscule performance hit of the concatenation, I prefer to keep things separate. This allows for greater control over potential changes later too :) Comes down to what you consider to be 'proper' capitalisation :) – haxxxton Nov 21 '16 at 06:02
2

If you are using jquery, use this code

function capitalize(str) {
    return str.charAt(0).toUpperCase() + str.slice(1);
}
var str = "my name is Jhon. are you good. is it";
var str1 = str.split('.');
var str2 = "";
$.each(str1,function(i){
   str2 += capitalize($.trim(str1[i]))+'. ';
});
console.log(str2);

catch the out put in str2. in my case its like the following.

My name is Jhon. Are you good. Is it.
Srinivas B
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