How to check for an "undefined" test present in the string using regex-Javascript

Question

I'm getting an undefined attached to a string at the end after a regex, something like:

var string="test.testA:(number:'1')undefined'

and sometimes it gets attached to the string as

var string2 = "test.testA:(number:'1') and undefined"

basically this could be anywhere and I wanted to remove this using regex. Does regex check if there is undefined present in the string? if not what is the best possible soln for this to remove the "undefined" test present in the string?

Thanks!

Do you want to remove just undefined or the whole string where it appears? — Toto
– Toto, Commented Aug 24, 2018 at 18:52

Toto · Accepted Answer · 2018-08-24 18:57:49Z

2

// remove only "undefined"
var test = [
    "test.testA:(number:'1')undefined",
    "test.testA:(number:'1') and undefined",
];
console.log(test.map(function (a) {
  return a.replace(/\bundefined\b/, '');
}));

// remove the whole line
var test2 = [
    "test.testA:(number:'1')undefined",
    "test.testA:(number:'1') and undefined",
];
console.log(test2.map(function (a) {
  return a.replace(/^.*?\bundefined\b.*$/, '');
}));

answered Aug 24, 2018 at 18:57

Toto

91.7k63 gold badges97 silver badges135 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

user8675309 · Accepted Answer · 2018-08-24 19:12:58Z

2

For both of your example strings this will remove everything after the close paren in the string.

var foo = inputString.replace(/[\w\s]*undefined\s*$/i, '');

\w - any of a-z, A-Z, 0-9, _
\s - spaces and tabs
[]* - 0 or more of any pattern inside
undefined - the literal "undefined"
\s* - 0 or more spaces/tabs
$ - end of the string
i - everything inside // is case-insensitive (the word 'undefined', in this case)

If you're looking to remove the entire contents of the input if it contains the word undefined then @Toto's answer is the way to go.

edited Aug 24, 2018 at 19:12

answered Aug 24, 2018 at 18:56

user8675309

6411 gold badge8 silver badges26 bronze badges

1 Comment

Jeff Over a year ago

Just clarifying for OP, this will remove everything after the last symbol (i.e. close parens)

Collectives™ on Stack Overflow

How to check for an "undefined" test present in the string using regex-Javascript

2 Answers 2

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related