Change occurrences of sum(something) to something_sum - javascript

Admittedly I'm terrible with RegEx and pattern replacements, so I'm wondering if anyone can help me out with this one as I've been trying now for a few hours and in the process of pulling my hair out.
Examples:
sum(Sales) needs to be converted to Sales_sum
max(Sales) needs to be converted to Sales_max
min(Revenue) needs to be converted to Revenue_min
The only available prefixed words will be sum, min, max, avg, xcount - not sure if this makes a difference in the solution.
Hopefully that's enough information to kind of show what I'm trying to do. Is this possible via RegEx?
Thanks in advance.

There are a few possible ways, for example :
var str = "min(Revenue)";
var arr = str.match(/([^(]+)\(([^)]+)/);
var result = arr[2]+'_'+arr[1];
result is then "Revenue_min".
Here's a more complex example following your comment, handling many matches and lowercasing the verb :
var str = "SUM(Sales) + MIN(Revenue)";
var result = str.replace(/\b([^()]+)\(([^()]+)\)/g, function(_,a,b){
return b+'_'+a.toLowerCase()
});
Result : "Sales_sum + Revenue_min"

Try with:
var input = 'sum(Sales)',
matches = input.match(/^([^(]*)\(([^)]*)/),
output = matches[2] + '_' + matches[1];
console.log(output); // Sales_sum
Also:
var input = 'sum(Sales)',
output = input.replace(/^([^(]*)\(([^)]*)\)/, '$2_$1');

You can use replace with tokens:
'sum(Sales)'.replace(/(\w+)\((\w+)\)/, '$2_$1')

Using a whitelist for your list of prefixed words:
output = input.replace(/\b(sum|min|max|avg|xcount)\((.*?)\)/gi,function(_,a,b) {
return b.toLowerCase()+"_"+a;
});
Added \b, a word boundary. This prevents something like "haxcount(xorz)" from becoming "haxorz_xcount"

Related

Using RegExp to substring a string at the position of a special character

Suppose I have a sting like this: ABC5DEF/G or it might be ABC5DEF-15 or even just ABC5DEF, it could be shorter AB7F, or AB7FG/H.
I need to create a javascript variable that contains the substring only up to the '/' or the '-'. I would really like to use an array of values to break at. I thought maybe to try something like this.
...
var srcMark = array( '/', '-' );
var whereAt = new RegExp(srcMark.join('|')).test.str;
alert("whereAt= "+whereAt);
...
But this returns an error: ReferenceError: Can't find variable: array
I suspect I'm defining my array incorrectly but trying a number of other things I've been no more successful.
What am I doing wrong?
Arrays aren't defined like that in JavaScript, the easiest way to define it would be with:
var srcMark = ['/','-'];
Additionally, test is a function so it must be called as such:
whereAt = new RegExp(srcMark.join('|')).test(str);
Note that test won't actually tell you where, as your variable suggests, it will return true or false. If you want to find where the character is, use String.prototype.search:
str.search(new RegExp(srcMark.join('|'));
Hope that helps.
You need to use the split method:
var srcMark = Array.join(['-','/'],'|'); // "-|/" or
var regEx = new RegExp(srcMark,'g'); // /-|\//g
var substring = "222-22".split(regEx)[0] // "222"
"ABC5DEF/G".split(regEx)[0] // "ABC5DEF"
From whatever i could understand from your question, using this RegExp /[/-]/ in split() function will work.
EDIT:
For splitting the string at all special characters you can use new RegExp(/[^a-zA-Z0-9]/) in split() function.
var arr = "ABC5DEF/G";
var ans = arr.split(/[/-]/);
console.log(ans[0]);
arr = "ABC5DEF-15";
ans = arr.split(/[/-]/);
console.log(ans[0]);
// For all special characters
arr = "AB7FG/H";
ans = arr.split(new RegExp(/[^a-zA-Z0-9]/));
console.log(ans[0]);
You can use regex with String.split.
It will look something like that:
var result = ['ABC5DEF/G',
'ABC5DEF-15',
'ABC5DEF',
'AB7F',
'AB7FG/H'
].map((item) => item.split(/\W+/));
console.log(result);
That will create an Array with all the parts of the string, so each item[0] will contain the text till the / or - or nothing.
If you want the position of the special character (non-alpha-numeric) you can use a Regular Expression that matches any character that is not a word character from the basic Latin alphabet. Equivalent to [^A-Za-z0-9_], that is: \W
var pattern = /\W/;
var text = 'ABC5DEF/G';
var match = pattern.exec(text);
var position = match.index;
console.log('character: ', match[0]);
console.log('position: ', position);

How to format string to mm/dd/yyyy with regex

I have been struggling with this particular regular expression and was wondering if anyone can help. I have an input field that allows users to enter text and if a user enters 01201990 I have a method that converts it to 01/20/19/90 The problem is I don't want the regular expression to continue after the mm/dd/ my end result would look like this 01/20/1990 Any help would be amazing.
var tmparray = [];
tmparray.push(
tmp.model
// here is where I dont know how to prevent the regex
// from continuing after 01/20/
.match(new RegExp('.{1,2}', 'g'))
.join("/")
);
tmp.model = tmparray;
console.log(tmp.model);
You can use replace() in this case
document.write('19101992'.replace(/(\d{2})(\d{2})(\d{4})/, '$1/$2/$3'))
Your code will be like
var tmparray = [];
tmparray.push(
tmp.model
// here is where I dont know how to prevent the regex
// from continuing after 01/20/
.replace(/(\d{2})(\d{2})(\d{4})/g, '$1/$2/$3')
);
tmp.model = tmparray;
console.log(tmp.model);
why not just match on:
/(\d{2})(\d{2})(\d{4})/
then dd/mm/yyyy is:
$1/$2/$3
(I can't see why you'd match {1,2} since you can't tell the difference between 1/11/1990 and 11/1/1990 and in either case would get 11/11/990...)
Try using String.prototype.slice() , String.prototype.concat()
var str = "01201990" , d = "/"
, res = str.slice(0,2).concat(d + str.slice(2,4)).concat(d + str.slice(4));
console.log(res)
use regex [0-9]{2}(?=(?:[0-9]{4})). for more information please check link https://www.safaribooksonline.com/library/view/regular-expressions-cookbook/9781449327453/ch06s12.html

JavaScript Match Using regexp

I'm trying to extract some data from a large string and I was wondering if it is possible to use regexp. Currently, I'm using javascript. For example:
This is some [example] text for my javascript [regexp] [lack] of knowledge.
With this string, I would like to generate a JSON array with the texts that are between the square brackets.
example, regexp, lack
I hope someone can help me do this in a simple way so I can understand how it works. Thank you in advance for your help. Daniel!
var str = "This is some [example] text for my javascript [regexp] [lack] of knowledge."
var regex = /\[(.*?)\]/g, result, indices = [];
while ( (result = regex.exec(str)) ) {
indices.push(result[1]);
}
var text = 'some [example] text for my javascript [regexp] [lack] of knowledge.';
text.match(/\[(.*?)\]/g).map(function(m) {
return m.substr(1, m.length - 2);
})
// => ["example", "regexp", "lack"]
http://jsfiddle.net/mE7EQ/
I wrote one up real quick, if you have any questions about it, let me know!
var a = 'This is some [example] text for my javascript [regexp] [lack] of knowledge.'
var results = a.match(/\[\w*\]/g);
alert(results[0] + ' ' + results[1] + ' ' + results[2]);

javascript split with regex

I would like to split characters into array using javascript with regex
foo=foobar=&foobar1=foobar2=
into
foo, foobar=,
foobar1, foobar2=
Sorry for not being clear, let me re describe the scenario.
First i would split it by "&" and want to post process it later.
str=foo=foobar=&foobar1=foobar2=
var inputvars=str.split("&")
for(i=0;i<inputvars.length;i++){
var param = inputvars[i].split("=");
console.log(param);
}
returns
[foo,foobar]
[]
[foobar1=foobar2]
[]
I tried to use .split("=") but foobar= got splited out as foobar.
I essentially want it to be
[foo,foobar=]
[foobar1,foobar2=]
Any help with using javascript to split first occurence of = only?
/^([^=]*)=(.*)/.exec('foo=foobar=&foobar1=foobar2=')
or simpler to write but using the newer "lazy" operator:
/(.*?)=(.*)/.exec('foo=foobar=&foobar1=foobar2=')
from malvolio, i got to conclusion below
var str = 'foo=foobar=&foobar1=foobar2=';
var inputvars = str.split("&");
var pattern = /^([^=]*)=(.*)/;
for (counter=0; counter<inputvars.length; counter++){
var param = pattern.exec(inputvars[counter]);
console.log(param)
}
and results (which is what i intended)
[foo,foobar=]
[foobar1,foobar2=]
Thanks to #malvolio hint of regex
Cheers

Remove everything after a certain character

Is there a way to remove everything after a certain character or just choose everything up to that character? I'm getting the value from an href and up to the "?", and it's always going to be a different amount of characters.
Like this
/Controller/Action?id=11112&value=4444
I want the href to be /Controller/Action only, so I want to remove everything after the "?".
I'm using this now:
$('.Delete').click(function (e) {
e.preventDefault();
var id = $(this).parents('tr:first').attr('id');
var url = $(this).attr('href');
console.log(url);
}
You can also use the split() function. This seems to be the easiest one that comes to my mind :).
url.split('?')[0]
jsFiddle Demo
One advantage is this method will work even if there is no ? in the string - it will return the whole string.
var s = '/Controller/Action?id=11112&value=4444';
s = s.substring(0, s.indexOf('?'));
document.write(s);
Sample here
I should also mention that native string functions are much faster than regular expressions, which should only really be used when necessary (this isn't one of those cases).
Updated code to account for no '?':
var s = '/Controller/Action';
var n = s.indexOf('?');
s = s.substring(0, n != -1 ? n : s.length);
document.write(s);
Sample here
var href = "/Controller/Action?id=11112&value=4444";
href = href.replace(/\?.*/,'');
href ; //# => /Controller/Action
This will work if it finds a '?' and if it doesn't
May be very late party :p
You can use a back reference $'
$' - Inserts the portion of the string that follows the matched substring.
let str = "/Controller/Action?id=11112&value=4444"
let output = str.replace(/\?.*/g,"$'")
console.log(output)
It works for me very nicely:
var x = '/Controller/Action?id=11112&value=4444';
var remove_after= x.indexOf('?');
var result = x.substring(0, remove_after);
alert(result);
If you also want to keep "?" and just remove everything after that particular character, you can do:
var str = "/Controller/Action?id=11112&value=4444",
stripped = str.substring(0, str.indexOf('?') + '?'.length);
// output: /Controller/Action?
You can also use the split() method which, to me, is the easiest method for achieving this goal.
For example:
let dummyString ="Hello Javascript: This is dummy string"
dummyString = dummyString.split(':')[0]
console.log(dummyString)
// Returns "Hello Javascript"
Source: https://thispointer.com/javascript-remove-everything-after-a-certain-character/
if you add some json syringified objects, then you need to trim the spaces too... so i add the trim() too.
let x = "/Controller/Action?id=11112&value=4444";
let result = x.trim().substring(0, x.trim().indexOf('?'));
Worked for me:
var first = regexLabelOut.replace(/,.*/g, "");
It can easly be done using JavaScript for reference see link
JS String
EDIT
it can easly done as. ;)
var url="/Controller/Action?id=11112&value=4444 ";
var parameter_Start_index=url.indexOf('?');
var action_URL = url.substring(0, parameter_Start_index);
alert('action_URL : '+action_URL);

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