I am trying to match a word which have either space before it or after it or both .

var sample = " test-abc -test# @test _test hello-test@ test test "

Like in the above case the first 'test' will count as it has a space before it, the next will not count as it has no space, the third 'test' will count as it has a space after it ,similarly the fourth one too, the fifth one will not count as it has no spaces front or back and the last two will as they have spaces before and after.

function countOccurences(str,word){
       var regex = new RegExp("(\\b|(?<=_))" word "(\\b|(?<=_))","gi");
       console.log((str.match(regex)|| []).length);
    }

The function I have written count the exact word but do not consider the space so the output I get is 7 but what I am trying to get is 5.

CodePudding user response：

You may try using match() here:

var sample = " test-abc -test# @test _test hello-test@ test test ";
var matches = sample.match(/(?<=\s)test|test(?=\s)/g, sample);
console.log("There were "   matches.length   " matches of test with whitespace on one side");

<iframe name="sif1" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

The regex pattern used here says to match:

(?<=\s)test  test preceded by whitespace
|            OR
test(?=\s)   test followed by whitespace

Note that the 5 matches here were:

test-abc
@test
_test
test
test