javascript variable contains instead of equals

Question

in a javascript if...else statement, instead of checking if a variable equals (==) a value, is it possible to check if a variable includes a value?

var blah = unicorns are pretty;
if(blah == 'unicorns') {};       //instead of doing this,
if(blah includes 'unicorns') {}; //can i do this?

also, the word it includes should be the FIRST word of the variable. Thanks!!!

And a "word" is the character sequence form the beginning of the string to the first space? What about `"unicornsuperpowers are great"`? — Felix Kling, Mar 01 '13 at 00:23

score 2 · Answer 1 · edited May 23 '17 at 11:49

If by "first word", you mean a character sequence from the beginning of the string to the first space, then this will do it:

if  ((sentence + ' ').indexOf('unicorns ') === 0) {
    //         note the trailing space ^
}

If instead of a space it can be any white-space character, you should use a regular expression:

if (/^unicorns(\s|$)/.test(sentence)) {
    // ...
}

// or dynamically
var search = 'unicorns';
if (RegExp('^' + search + '(\\s|$)').test(sentence)) {
    // ...
}

You can also use the special word-boundary character, depending on the language you want to match:

if (/^unicorns\b/.test(sentence)) {
    // ...  
}

More about regular expressions.

Related question:

How to check if a string "StartsWith" another string?

Alex · Accepted Answer · 2013-03-01T00:28:27.163

1

if(blah.indexOf('unicorns') == 0) {
    // the string "unicorns" was first in the string referenced by blah.
}

if(blah.indexOf('unicorns') > -1) {
    // the string "unicorns" was found in the string referenced by blah.
}

indexOf

To remove the first occurrence of a string:

blah = blah.replace('unicorns', '');

edited Mar 01 '13 at 00:28

answered Mar 01 '13 at 00:20

Alex

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@ThomasLai: http://stackoverflow.com/questions/5095000/jquery-remove-string-from-string. – Felix Kling Mar 01 '13 at 00:34

score 1 · Answer 3 · answered Mar 01 '13 at 00:25

1

You can also use a quick regex test:

if (/unicorns/.test(blah)) {
  // has "unicorns"
}

answered Mar 01 '13 at 00:25

elclanrs

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To check the *first* word you would need `if (/^unicorns/.test(blah))` – Andrew Kirkegaard Mar 01 '13 at 00:31

javascript variable contains instead of equals

3 Answers3