JS how to check empty String and Space [duplicate]

Question

Help me pls

if(value == ""){
// do anything
}

but I need to check space " " (2,3,... space is include) is the same way of empty String

ps. sorry in my English

@Andrew - It's not a duplicate at all. That other question has nothing to do with detecting strings containing only spaces. — RJM
– RJM, Commented Apr 8, 2016 at 3:40
@RJM There are numerous answers on that question that handle: null/undefined and only-whitespace input. See, for example, this answer — Andrew
– Andrew, Commented Apr 8, 2016 at 3:45
sorry man I need to check String with whitespace only is same as empty String — JinkleBell Surcharoen
– JinkleBell Surcharoen, Commented Apr 8, 2016 at 3:45

castletheperson · Accepted Answer · 2021-07-21 14:43:01Z

12

A regex can easily solve this problem.

if (/^ *$/.test(value)) {
    //string contains 0+ spaces only
}

If you need to include null also, then add !value ||.

If you need to include newlines, tabs, and the like, then use /^\s*$/ for the regex.

answered Apr 8, 2016 at 3:44

castletheperson

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1 Comment

Why regex and not if (!value || !value.trim()) { //null or empty }. Matches empty strings, tabs, newline characters