CODEWITHSUNDEEP
javascriptregexreplacelowercase
user3105222
user3105222

Reputation:

Why toLowerCase() does not work with a regexp?

This:

replace(/([a-zA-Z])([A-Z]+)/g,'$1'+'$2'.toLowerCase() )

Does not convert $2 to lowercase (unchanged)

But :

replace(/([a-zA-Z])([A-Z]+)/g,'$1'+'heLLo'.toLowerCase() )

Makes every upper case being replaced by "hello" (as expected)

Why?

Thanks.

Upvotes: 0

Views: 171

Answers (1)

durum
durum

Reputation: 3404

Because toLowerCase is executed before it gets in the main function replace. This is what you are doing:

replace(/([a-zA-Z])([A-Z]+)/g,'$1hello')

You can do what you want with this:

var replaceLogic = function(fullMatch, firstGroup, secondGroup){ 
    return firstGroup.toLowerCase() + secondGroup; 
};
string.replace(/([a-zA-Z])([A-Z]+)/g, replaceLogic);

Upvotes: 2

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