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Find index number of array value based on partial string match

I have been stuck on this as I am not the best with mixing arrays + string matches.
What I would like to do is return the index number within an array based on a partial match from a string. Full use case; check if text exists in a URL based off values within an array - and return the index of array position.
Don't mind JS or jQuery but whichever might be most efficient is fine (or works).
Current attempt:
Example URL = www.site.com/something/car/123
Another Example URL might be www.site.com/something/somethingelse/banana/
(location of snippet to match is not always in the same path location)
var pageURL = location.href;
var urlArray = ['/car/','/boat/','/apple/','/banana/'];
function contains(urlArray, value) {
var i = urlArray.length;
while (i--) { if (urlArray[i].indexOf(pageURL)) console.log(i)} console.log('Not Found');}
alternate Using jQuery (not sure where to use indexOf or another jQuery alternative (.search / .contains)):
urlArray.each(function(){
$.each(this, function(index) { } ) });
Expected output for first URL would be 0, second example URL would be 3.
Help is much appreciated!

You can iterate over the array with findIndex() to get the index if the includes() the string.
This will go through the urlArray and return the index of the first match (and -1 if a match isn't found).
let URL1 = "www.site.com/something/car/123"
let URL2 = "www.site.com/something/somethingelse/banana/"
let urlArray = ['/car/','/boat/','/apple/','/banana/'];
let index1 = urlArray.findIndex(str => URL1.includes(str))
let index2 = urlArray.findIndex(str => URL2.includes(str))
console.log(index1, index2)

You can also use a forEach() loop on the urlArray to get each word from the array and check if it exist in url or not.
var url = 'www.site.com/car/somethingelse/banana/';
var urlArray = ['/car/', '/boat/', '/apple/', '/banana/'];
urlArray.forEach(function(word){
//if word exist in url
var wordIndex = url.indexOf(word);
if(wordIndex !== -1){
console.log(wordIndex);
}
});
NOTE includes() do not work in IE browser and older versions thus to make it work on all browsers the recommended way is to avoid arrow functions with includes() and instead use plain function with indexOf()
To return the array index:
var url = 'www.site.com/car/somethingelse/banana/';
var urlArray = ['/car/', '/boat/', '/apple/', '/banana/'];
urlArray.forEach(function(word, index){
//if word exist in url
if(url.indexOf(word) !== -1){
console.log(index);
}
});

for (var i = 0; i < urlArray.length; i++) {
if(pageURL .indexOf(urlArray[i])>-1){
console.log(pageURL.indexOf(urlArray[i])));
}
}

Matching anagrams and pushing to an array

I have a given word, that I want to match against a given list of words, mainList, and establish which words of that given list are anagrams of the given word, and add them to another list, subList.
I feel like my method to do this is fine, but it returns an unexpected result.
For example...
var word = 'master';
var mainList = ['stream', 'pidgeon', 'maters'];
var subList = [];
Then I take the word, split to an array of letters, alphabetise, and join back into a string. With this string I should be able match against any possible anagrams (which I will covert in the same way).
var mainSorted = [];
for (i = 0; i < word.length; i++) {
mainSorted = word.split('').sort().join();
}
This is where it goes wrong. I loop through the mainList array trying to establish if a given item, when converted, matches the original. If so, I want to push the word to the subList array.
for (var i = 0; i < mainList.length; i++) {
var subSorted = mainList[i].split('').sort().join;
if (mainSorted === subSorted) {
subList.push(mainList[i])
}
}
return subList;
...and the value I expect to see for subList is: ['stream', 'maters']
Yet I am returned an empty array instead.
I've gone through this so many times and I cannot see what's going wrong, would really appreciate some help!
Also, I'm aware there's probably more eloquent methods to do this (and I welcome any suggestions) but primarily I want to see where this is going wrong.
Thanks in advance.

You forgot () at the end of join
var subSorted = mainList[i].split('').sort().join;
should be
var subSorted = mainList[i].split('').sort().join();
One non-issue is
for (i = 0; i < word.length; i++) {
mainSorted = word.split('').sort().join();
}
doesnt need to be in a loop
mainSorted = word.split('').sort().join();
alone suffices
as a bonus, here's a tidier way of doing what you are doing
var word = 'master';
var mainList = ['stream', 'pidgeon', 'maters'];
var mainSorted = word.split('').sort().join();
return mainList.filter(function(sub) {
return sub.split('').sort().join() == mainSorted;
});

access elements in array of strings that contain certain strings

I have an array that can look like this: ["whatWP", "isVBZ", "theDT", "temperatureNN", "inIN", "bostonNN"]
I want to access the element containing IN, if it exists and the next elements(s) until I reach and including an element with NN in it. and join those elements together into a string.
When I try to access the element containing IN like so, I get -1 that there is no element containing IN.
Here's how I am trying to do it:
strARR = ["whatWP", "isVBZ", "theDT", "temperatureNN", "inIN", "bostonNN"];
strARR[strARR.indexOf('IN')];
but then I get undefined because nothing at -1 exists.
How can I access the element of this array of strings if it contains IN and every element after until it matches an element containing NN, including that element? And joining those as a string?

You need a for loop for that:
var strARR = ["whatWP", "isVBZ", "theDT", "temperatureNN", "inIN", "bostonNN"];
var foundStr = null;
for (var i = 0, cString; i < strARR.length; ++i) {
cString = strARR[i];
if (cString.indexOf("IN") !== -1) {
foundStr = cString;
break;
}
}
if (foundStr !== null) {
/* do someting with found string */
}
strARR[strARR.indexOf('IN')] was returning a weird value because:
strARR.indexOf('IN') // returns -1 (no string "IN" in the array)
strArr[-1] // undefined

There is no "IN" element in that array. Just an "inIN" element, which is not precisely equal. (Keep in mind, this could be an array of ANYTHING, not just strings, so it's not assumed they can check the string contents)
You'll have to loop through the strARR, using a standard for(var i = 0; i < strARR.length; i++) loop. The i variable will help you find the correct indexes.
Then, for combining the results, use the Array.splice and Array.join methods. Splice can take a start index and length of items to take as arguments, and Join can take an intermediate character as an argument, like a comma, to put between them.

You need to evaluate each element in the array individually, not evaluate the array as a whole. Using jQuery each, you can do:
var containsIN = '';
$.each(strARR, function(){
if($(this).indexOf('IN') !== -1){
containsIN = $(this);
}
});
To achieve appending or joining string until you find a string that contains 'NN'
you need to modify the original if condition to:
if(containsIN === '' && $(this).indexOf('IN') !== -1)
then add another condition afterwards
if(containsIN !== ''){
final += $(this);
}
Then, to terminate the each:
if($(this).indexOf('NN') !== -1){
return false;
}
So, the final code should look like:
var containsIN = '';
var final = '';
$.each(strARR, function(){
if(containsIN === '' && $(this).indexOf('IN') !== -1){
containsIN = $(this);
}
if(containsIN !== ''){
final += $(this);
}
if($(this).indexOf('NN') !== -1){
return false;
}
});

You can use the Array's filter() function for this. There is a polyfill available on the linked page if you need to target browsers that do not support filter() natively.
You can create any filter condition that you like and filter() will return the array elements that match your condition.
var strARR = ["whatWP", "isVBZ", "theDT", "temperatureNN", "inIN", "bostonNN"];
var strARRFiltered = strARR.filter(function(element){
return element.indexOf("IN") !== -1;
});
alert(strARRFiltered);
Here is an example of this concept expanded a bit to include accessing multple matches and a variable filter.

To do what you're currently trying to do, the code would need to be like this:
strARR = ["whatWP", "isVBZ", "theDT", "temperatureNN", "inIN", "bostonNN"];
strARR[strARR.indexOf('inIN')];
You need to loop through each element in the array calling indexOf, rather than trying to access it as an array.

How to split a comma separated string and process in a loop using JavaScript

How to split a comma separated string and process in a loop using JavaScript?

My two cents, adding trim to remove the initial whitespaces left in sAc's answer.
var str = 'Hello, World, etc';
var str_array = str.split(',');
for(var i = 0; i < str_array.length; i++) {
// Trim the excess whitespace.
str_array[i] = str_array[i].replace(/^\s*/, "").replace(/\s*$/, "");
// Add additional code here, such as:
alert(str_array[i]);
}
Edit:
After getting several upvotes on this answer, I wanted to revisit this. If you want to split on comma, and perform a trim operation, you can do it in one method call without any explicit loops due to the fact that split will also take a regular expression as an argument:
'Hello, cruel , world!'.split(/\s*,\s*/);
//-> ["Hello", "cruel", "world!"]
This solution, however, will not trim the beginning of the first item and the end of the last item which is typically not an issue.
And so to answer the question in regards to process in a loop, if your target browsers support ES5 array extras such as the map or forEach methods, then you could just simply do the following:
myStringWithCommas.split(/\s*,\s*/).forEach(function(myString) {
console.log(myString);
});

Like this:
var str = 'Hello, World, etc';
var myarray = str.split(',');
for(var i = 0; i < myarray.length; i++)
{
console.log(myarray[i]);
}

Try the following snippet:
var mystring = 'this,is,an,example';
var splits = mystring.split(",");
alert(splits[0]); // output: this
Edit:
The following snippet will allow you to split, manipulate each element and get the results in an array:
const string = "this,is,a,string";
const array = string.split(",")
.map((item, i) => `Item ${i} => ${item}`);
console.log(array)

Please run below code may it helps you :)
var str = "this,is,an,example";
var strArr = str.split(',');
var data = "";
for(var i=0; i<strArr.length; i++){
data += "Index : "+i+" value : "+strArr[i]+"<br/>";
}
document.getElementById('print').innerHTML = data;
<div id="print">
</div>

you can Try the following snippet:
var str = "How are you doing today?";
var res = str.split("o");
console.log("My Result:",res)
and your output like that
My Result: H,w are y,u d,ing t,day?

Example using async/await in a forEach loop:
const files = "name1,name2,name3"
if (files.length) {
await forEachAsync(files.toString().split(','), async (item) => {
console.log(item)
});

How to do multiple regular expressions, each time refining the results?

Why can't I output my regex to a variable, and then run regex on it a second time?
I'm writing a greasemonkey javascript that grabs some raw data, runs some regex on it, then runs some more regex on it to refine the results:
// I tried this on :: http://stackoverflow.com/
var tagsraw = (document.getElementById("subheader").innerHTML);
alert(tagsraw);
Getting the raw data (above code) works
var trimone = tagsraw.match(/title\W\W\w+\s\w+\s\w+\s\w+\s\w+/g);
alert(trimone);
running regex once works (above code); but running (code below) doesn't??
var trimtwo = trimone.match(/\s\w+\s\w+\s\w+\s\w+/g);
alert(trimtwo);
Can some advise me as to what is wrong with my code/approach?

The reason the first match works, is because innerHTML returns a string.
However the match returns an array, thus treat it as one:
for (var i=0; i<trimone.length; i++)
{
var trimtwo = trimone[i].match(/\s\w+\s\w+\s\w+\s\w+/g);
alert(trimtwo);
}
Edit:
Try this code instead though, I think this is a bit closer to what you want to achieve:
var trimone = tagsraw.match(/title\s*=\s*".*"/g);
alert(trimone);
for (var i=0; i<trimone.length; i++)
{
alert(trimone[i]);
}

You could do something like this:
var str = "<title> foo bar baz quux blah</title>",
re = [
/title\W\W\w+\s\w+\s\w+\s\w+\s\w+/g,
/\s\w+\s\w+\s\w+\s\w+/g
],
tmp = [str];
for (var i=0, n=re.length; i<n; ++i) {
tmp = tmp.map(function(val) {
return val.match(re[i])[0];
});
}
alert(tmp);

.match should be returning an array, not a string.

Your case is better suited to using .exec. You could even chain the two if you don't care about the intermediate result:
/\s\w+\s\w+\s\w+\s\w+/g.exec(/title\W\W\w+\s\w+\s\w+\s\w+\s\w+/g.exec(tagsraw));

The problem is that match() returns an array and there is no built-in function to perform a regular expression on an array.
So instead you should be able to do this with the exec function from the Regexp object. It will return the matched string. You can grab the matched string from the first regexp and use it for the second.
So it'd be something like this:
var patt1 = new Regexp(/title\W\W\w+\s\w+\s\w+\s\w+\s\w+/g);
var trimone = patt1.exec(tagsraw);
if (trimone != null) // might be null if no match is found
{
alert(trimone);
var patt2 = new Regexp(/\s\w+\s\w+\s\w+\s\w+/g);
var trimtwo = patt2.exec(trimone);
alert(trimtwo);
}
Note that exec returns null if no match is found so be sure to handle that in your code like I do above.