I have this string defined
const str : string = 'hostel:uk>london>city>street';
that I want to split to see only hostel, but I see the whole string in the console
console.log(str.split([":"][1]));
You could match the first part until colon.
const
str = 'hostel:uk>london>city>street',
first = str.match(/^[^:]+/)[0];
console.log(first);
You need to put the [] after the split() as the output of a split() is an array.
So your code will change to,
console.log(str.split([":"])[0]);
Also, after the split(), "hostel" will be at the 0th index of the array.
You need to select item 0, and also do that after the split call (not inside it), and you need to pass a string into split:
console.log(str.split(":")[0]);
you can perform your desired output after adding this line
console.log(str.split(':')[0]);
Related
I have a URL from which I want to remove the substring after the second dot.
input:
google.com/xyz.abc.html
output:
google.com/xyz
The following regex works, but not sure this is the right way to do it
^([\w/]+\.[\w/]+\.)
You can use split and join, 2nd argument inside split is to limit the number of chunks, i.e here it will only output 2 element in resulting array
console.log(`google.com/xyz.abc.html`.split('.',2).join('.'))
Here is a non regex solution for this.
let inp = 'google.com/xyz.abc.html';
let out = [inp.split('/')[0], inp.split('/')[1].split('.')[0]].join('/');
console.log(out);
I'm trying to split a TitleCase (or camelCase) string into precisely two parts using javascript. I know I can split it into multiple parts by using the lookahead:
"StringToSplit".split(/(?=[A-Z])/);
And it will make an array ['String', 'To', 'Split']
But what I need is to break it into precisely TWO parts, to produce an array like this:
['StringTo', 'Split']
Where the second element is always the last word in the TitleCase, and the first element is everything else that precedes it.
Is this what you are looking for ?
"StringToSplit".split(/(?=[A-Z][a-z]+$)/); // ["StringTo", "Split"]
Improved based on lolol answer :
"StringToSplit".split(/(?=[A-Z][^A-Z]+$)/); // ["StringTo", "Split"]
Use it like this:
s = "StringToSplit";
last = s.replace(/^.*?([A-Z][a-z]+)(?=$)/, '$1'); // Split
first = s.replace(last, ''); // StringTo
tok = [first, last]; // ["StringTo", "Split"]
You could use
(function(){
return [this.slice(0,this.length-1).join(''), this[this.length-1]];
}).call("StringToSplit".split(/(?=[A-Z])/));
//=> ["StringTo", "Split"]
In [other] words:
create the Array using split from a String
join a slice of that Array without the last element of that
Array
add that and the last element to a final Array
I need to take a string and get some values from it. I have this string:
'tab/tab2/tab3'
The '/tab3' is optional so this string should also work:
'tab/tab2'
I currently am trying this which works for the most part:
'tab/tab2/tab3'.match(new RegExp('^tab/([%a-zA-Z0-9\-\_\s,]+)(/([%a-zA-Z0-9-_s,]+)?)$'));
This will return:
["tab/tab2/tab3", "tab2", "/tab3", "tab3"]
but I want it to return
["tab/tab2/tab3", "tab2", "tab3"]
So I need to get rid of the 3rd index item ("/tab3") and also get it to work with just the 'tab/tab2' string.
To complicate it even more, I only have control over the /([%a-zA-Z0-9-_s,]+)? part in the last grouping meaning it will always wrap in a grouping.
you don't need regex for this, just use split() method:
var str = 'tab/tab2/tab3';
var arr = str.split('/');
console.log(arr[0]); //tab
console.log(arr[1]); //tab2
jsfiddle
I used this regexp to do this:
'tab/tab2/tab3'.match(new RegExp('^tab/([%a-zA-Z0-9\-\_\s,]+)(?:/)([%a-zA-Z0-9-_s,]+)$'));
Now I get this return
["tab/tab2/tab3", "tab2", "tab3"]
Now I just need to allow 'tab/tab2' to be accepted aswell...
Do not put regex between " or ', using /g to make global search else only first occurrence is returned
"tab/tab2/tab3".match(/tab[0-9]/g)
I don't understand this behaviour:
var string = 'a,b,c,d,e:10.';
var array = string.split ('.');
I expect this:
console.log (array); // ['a,b,c,d,e:10']
console.log (array.length); // 1
but I get this:
console.log (array); // ['a,b,c,d,e:10', '']
console.log (array.length); // 2
Why two elements are returned instead of one? How does split work?
Is there another way to do this?
You could add a filter to exclude the empty string.
var string = 'a,b,c,d,e:10.';
var array = string.split ('.').filter(function(el) {return el.length != 0});
A slightly easier version of #xdazz version for excluding empty strings (using ES6 arrow function):
var array = string.split('.').filter(x => x);
This is the correct and expected behavior. Given that you've included the separator in the string, the split function (simplified) takes the part to the left of the separator ("a,b,c,d,e:10") as the first element and the part to the rest of the separator (an empty string) as the second element.
If you're really curious about how split() works, you can check out pages 148 and 149 of the ECMA spec (ECMA 262) at http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-262.pdf
Use String.split() method with Array.filter() method.
var string = 'a,b,c,d,e:10.';
var array = string.split ('.').filter(item => item);
console.log(array); // [a,b,c,d,e:10]
console.log (array.length); // 1
https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/String/split
trim the trailing period first
'a,b,c,d,e:10.'.replace(/\.$/g,''); // gives "a,b,c,d,e:10"
then split the string
var array = 'a,b,c,d,e:10.'.replace(/\.$/g,'').split('.');
console.log (array.length); // 1
That's because the string ends with the . character - the second item of the array is empty.
If the string won't contain . at all, you will have the desired one item array.
The split() method works like this as far as I can explain in simple words:
Look for the given string to split by in the given string. If not found, return one item array with the whole string.
If found, iterate over the given string taking the characters between each two occurrences of the string to split by.
In case the given string starts with the string to split by, the first item of the result array will be empty.
In case the given string ends with the string to split by, the last item of the result array will be empty.
It's explained more technically here, it's pretty much the same for all browsers.
According to MDN web docs:
Note: When the string is empty, split() returns an array containing
one empty string, rather than an empty array. If the string and
separator are both empty strings, an empty array is returned.
const myString = '';
const splits = myString.split();
console.log(splits);
// ↪ [""]
Well, split does what it is made to do, it splits your string. Just that the second part of the split is empty.
Because your string is composed of 2 part :
1 : a,b,c,d,e:10
2 : empty
If you try without the dot at the end :
var string = 'a,b,c:10';
var array = string.split ('.');
output is :
["a,b,c:10"]
You have a string with one "." in it and when you use string.split('.') you receive array containing first element with the string content before "." character and the second element with the content of the string after the "." - which is in this case empty string.
So, this behavior is normal. What did you want to achieve by using this string.split?
try this
javascript gives two arrays by split function, then
var Val = "abc#gmail.com";
var mail = Val.split('#');
if(mail[0] && mail[1]) { alert('valid'); }
else { alert('Enter valid email id'); valid=0; }
if both array contains length greater than 0 then condition will true
I tried use javascript spilt to get part of the word : new from What#a_new%20day
I tried code like this:
<script>
var word="What#a_new%20day";
var newword = word.split("%20", 1).split("_", 2);
alert(newword);
</script>
But caused:
Uncaught TypeError: Object What#a_new has no method 'split'
Maybe there have more wiser way to get the word which I need. So can anyone help me? Thanks.
split returns an array, so the second split is trying to operate on the array returned by the first, rather than a string, which causes a TypeError. You'll also want to add the correct index after the second call to split, or newword will also be an array, not the String you're expecting. Change it to:
var newword = word.split("%20", 1)[0].split("_", 2)[1];
This splits word, then splits the string at index 0 of the resulting array, and assigns the value of the string at index 1 of the new array to newword.
Regex to the rescue
var word="What#a_new%20day";
var newword = word.match(/_(.+)%/)[1];
alert(newword);
this returns the first ([1]) captured group ((...)) in the regex (_(.+)%) which is _ followed by any character (.) one or more times (+) followed by %.
the result of a split is an array, not a string. so what you need to do is
<script>
var word="What#a_new%20day";
var newword = word.split("%20", 1)[0].split("_", 2);
alert(newword);
</script>
notice the [0]
split returns an array:
https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/String/split
word.split("%20", 1);
gives an array so you cannot do :
(result from above).split("_", 2);
If split is what your after, go for it, but performance wise, it would be better to do something like this:
var word="What#a_new%20day";
var newword = word.substr(word.indexOf('new'),3)
alert(newword);
Live example: http://jsfiddle.net/qJ8wM/
Split searches for all instances of %20 in the text, whereas indexOf finds the first instance, and substr is fairly cheap performance wise as well.
JsPerf stats on split vs substring (a general case): http://jsperf.com/split-vs-substring