We Keep Coding

How to remove `&` sign and all text after that from url

I have this URL
https://myApp-ajj.com/sp?id=cat_item&sys_id=cf9f149cdbd25f00d080591e5e961920&sys_id1=cf9f149cdbd25f00d080591e5e961920&sysp_Id=a691acd9dbdf1bc0e9619fb&sysparm_CloneTable=sc_request&sysparm_CloneTable=sc_request
Here I am getting sys_id two times with different parameters. So I need to remove the second & sign and all text after that.
I tried this
location.href.split('&')[2]
I am sure it doesn't work. Can anyone provide some better solution?

Firstly, you should split the string into an array then use slice to set the starting index number of the element which is 2 in your case and then join the array again into the string.
Read more about these methods JavaScript String split() Method, jQuery slice() Method and JavaScript Array join() Method
var url = 'https://myApp-ajj.com/sp?id=cat_item&sys_id=cf9f149cdbd25f00d080591e5e961920&sys_id=cf9f149cdbd25f00d080591e5e961920&sysp_Id=a691acd9dbdf1bc0e9619fb&sysparm_CloneTable=sc_request&sysparm_CloneTable=sc_request';
url = url.split("&").slice(0,2).join("&");
console.log(url);

Maybe like this:
var url='https://myApp-ajj.com/sp?id=cat_item&sys_id=cf9f149cdbd25f00d080591e5e961920&sys_id=cf9f149cdbd25f00d080591e5e961920&sysp_Id=a691acd9dbdf1bc0e9619fb&sysparm_CloneTable=sc_request&sysparm_CloneTable=sc_request';
var first=url.indexOf('&');
var second=url.indexOf('&',first+1);
var new_url=url.substring(0,second);
console.log(new_url);

You need to find the 2nd occurrence of &sys_id. From there onwards remove all text.
Below is working code:
let url='https://myApp-ajj.com/sp?id=cat_item&sys_id=cf9f149cdbd25f00d080591e5e961920&sys_id=cf9f149cdbd25f00d080591e5e961920&sysp_Id=a691acd9dbdf1bc0e9619fb&sysparm_CloneTable=sc_request&sysparm_CloneTable=sc_request';
let str1=url.indexOf('&sys_id');
let str2=url.indexOf('&sys_id',str1+1);
console.log(url.substring(0,str2));

This is a bit more verbose, but it handles all duplicate query params regardless of their position in the URL.
function removeDuplicateQueryParams(url) {
var params = {};
var parsedParams = '';
var hash = url.split('#'); // account for hashes
var parts = hash[0].split('?');
var origin = parts[0];
var retURL;
// iterate over all query params
parts[1].split('&').forEach(function(param){
// Since Objects can only have one key of the same name, this will inherently
// filter out duplicates and keep only the latest value.
// The key is param[0] and value is param[1].
param = param.split('=');
params[param[0]] = param[1];
});
Object.keys(params).forEach(function(key, ndx){
parsedParams += (ndx === 0)
? '?' + key +'='+ params[key]
: '&' + key +'='+ params[key];
});
return origin + parsedParams + (hash[1] ? '#'+hash[1] : '');
}
console.log( removeDuplicateQueryParams('http://fake.com?q1=fu&bar=fu&q1=fu&q1=diff') );
console.log( removeDuplicateQueryParams('http://fake.com?q1=fu&bar=fu&q1=fu&q1=diff#withHash') );

var url = "https://myApp-ajj.com/sp?id=cat_item&sys_id=cf9f149cdbd25f00d080591e5e961920&sys_id1=cf9f149cdbd25f00d080591e5e961920&sysp_Id=a691acd9dbdf1bc0e9619fb&sysparm_CloneTable=sc_request&sysparm_CloneTable=sc_request"
url = url.slice(0, url.indexOf('&', url.indexOf('&') + 1));
console.log(url);
Try this :)

Try this:
var yourUrl = "https://myApp-ajj.com/sp?id=cat_item&sys_id=cf9f149cdbd25f00d080591e5e961920&sys_id=cf9f149cdbd25f00d080591e5e961920&sysp_Id=a691acd9dbdf1bc0e9619fb&sysparm_CloneTable=sc_request&sysparm_CloneTable=sc_request"
var indexOfFirstAmpersand = yourUrl.search("&"); //find index of first &
var indexOfSecondAmpersand = indexOfFirstAmpersand + yourUrl.substring((indexOfFirstAmpersand + 1)).search("&") + 1; //get index of second &
var fixedUrl = yourUrl.substring(0, indexOfSecondAmpersand)
$(".answer").text(fixedUrl);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<p class="answer">
</p>

You can manipulate the url using String.prototype.substring method. In the example below I created a function that takes a url string and checks for a duplicate parameter - it returns a new string with the second occurrence removed.
var url = "https://myApp-ajj.com/sp?id=cat_item&sys_id=cf9f149cdbd25f00d080591e5e961920&sys_id=cf9f149cdbd25f00d080591e5e961920&sysp_Id=a691acd9dbdf1bc0e9619fb&sysparm_CloneTable=sc_request&sysparm_CloneTable=sc_request";
function stripDuplicateUrlParameter(url, parameterName) {
//get the start index of the repeat occurrance
var repeatIdx = url.lastIndexOf('sys_id');
var prefix = url.substring(0, repeatIdx);
var suffix = url.substring(repeatIdx);
//remove the duplicate part from the string
suffix = suffix.substring(suffix.indexOf('&') + 1);
return prefix + suffix;
}
console.log(stripDuplicateUrlParameter(url));
This solves your specific problem, but wouldn't work if the parameter occurred more than twice or if the second occurrence of the string wasn't immediately following the first - you would probably write something more sophisticated.
As someone already asked - why is the url parameter being duplicated in the string anyway? Is there some way to fix that? (because the question asked seems to me to be a band-aid solution with this being the root issue).

Update uri hash javascript

I find it hard to believe this hasn't been asked but I can find no references anywhere. I need to add a URI hash fragment and update the value if it already is in the hash. I can currently get it to add the hash but my regex doesn't appear to catch if it exists so it adds another instead of updating.
setQueryString : function() {
var value = currentPage;
var uri = window.location.hash;
var key = "page";
var re = new RegExp("([#&])" + key + "=.*#(&|$)", "i");
var separator = uri.indexOf('#') !== -1 ? "&" : "#";
if (uri.match(re)) {
return uri.replace(re, '$1' + key + "=" + value + '$2');
}
else {
return uri + separator + key + "=" + value;
}
},
Also if this can be made any cleaner while preserving other url values/hashes that would be great.
example input as requested
Starting uri value:
www.example.com#page=1 (or no #page at all)
then on click of "next page" setQueryString gets called so the values would equal:
var value = 2;
var uri = '#page1'
var key = 'page'
So the hopeful output would be '#page2'.

As to your regex question, testing if the pattern #page=(number) or &page=(number) is present combined with capturing the number, can be done with the regex /[#&]page\=(\d*)/ and the .match(regex) method. Note that = needs escaping in regexes.
If the pattern exists in the string, result will contain an array with the integer (as a string) at result[1]. If the pattern does not exist, result will be null.
//match #page=(integer) or &page=(integer)
var test = "#foo=bar&page=1";
var regex = /[#&]page\=(\d*)/;
var result = test.match(regex);
console.log(result);
If you want to dynamically set the key= to something other than "page", you could build the regex dynamically, like the following (note that backslashes needs escaping in strings, making the code a bit more convoluted):
//dynamically created regex
var test = "#foo=bar&page=1";
var key = "page"
var regex = new RegExp("[#&]" + key + "\\=(\\d*)");
var result = test.match(regex);
console.log(result);

How to parse a url using Javascript and Regular Expression?

I want to parse some urls's which have the following format :-
var url ="http://www.example.com/cooks/cooking-dress-wine/~no-order/pr?p%5B%5D=sort%3Dfeatured&sid=bks%2C43p&mycracker=ch_vn_clothing_subcategory_Puma&ref=b41c8097-8efe-4acf-8919-0fa81bcb590a"
Its not necessary that the domain name and other parts would be same for all url's, they can vary i.e I am looking at a general solution.
Basically I want to strip off all the other things and get only the part:
/cooks/cooking-dress-wine/~no-order/pr?p%5B%5D=sort%3Dfeatured&sid=bks%2C43p
I thought to parse this using JavaScript and Regular Expression
I am doing like this:
var mapObj = {"/^(http:\/\/)?.*?\//":"","(&mycracker.+)":"","(&ref.+)":""};
var re = new RegExp(Object.keys(mapObj).join("|"),"gi");
url = url.replace(re, function(matched){
return mapObj[matched];
});
But its returning this
http://www.example.com/cooks/cooking-dress-wine/~no-order/pr?p%5B%5D=sort%3Dfeatured&sid=bks%2C43pundefined
Where am I not doing the correct thing? Or is there another approach with an even easier solution?

You can use :
/(?:https?:\/\/[^\/]*)(\/.*?)(?=\&mycracker)/
Code :
var s="http://www.example.com/cooks/cooking-dress-wine/~no-order/pr?p%5B%5D=sort%3Dfeatured&sid=bks%2C43p&mycracker=ch_vn_clothing_subcategory_Puma&ref=b41c8097-8efe-4acf-8919-0fa81bcb590a";
var ss=/(?:https?:\/\/[^\/]*)(\/.*?)(?=\&mycracker)/;
console.log(s.match(ss)[1]);
Demo
Fiddle Demo
Explanation :

Why don't you just map a split array?
You don't quite need to regex the URL, but you will have to run an if statement inside the loop to remove specific GET params from them. In this particular case (key word particular) you just have to substring till the indexOf "&mycracker"
var url ="http://www.example.com/cooks/cooking-dress-wine/~no-order/pr?p%5B%5D=sort%3Dfeatured&sid=bks%2C43p&mycracker=ch_vn_clothing_subcategory_Puma&ref=b41c8097-8efe-4acf-8919-0fa81bcb590a"
var x = url.split("/");
var y = [];
x.map(function(data,index) { if (index >= 3) y.push(data); });
var path = "/"+y.join("/");
path = path.substring(0,path.indexOf("&mycracker"));

Change the following code a little bit and you can retrieve any parameter:
var url = "http://www.example.com/cooks/cooking-dress-wine/~no-order/pr?p%5B%5D=sort%3Dfeatured&sid=bks%2C43p&mycracker=ch_vn_clothing_subcategory_Puma&ref=b41c8097-8efe-4acf-8919-0fa81bcb590a"
var re = new RegExp(/http:\/\/[^?]+/);
var part1 = url.match(re);
var remain = url.replace(re, '');
//alert('Part1: ' + part1);
var rf = remain.split('&');
// alert('Part2: ' + rf);
var part2 = '';
for (var i = 0; i < rf.length; i++)
if (rf[i].match(/(p%5B%5D|sid)=/))
part2 += rf[i] + '&';
part2 = part2.replace(/&$/, '');
//alert(part2)
url = part1 + part2;
alert(url);

var url ="http://www.example.com/cooks/cooking-dress-wine/~no-order/pr?p%5B%5D=sort%3Dfeatured&sid=bks%2C43p&mycracker=ch_vn_clothing_subcategory_Puma&ref=b41c8097-8efe-4acf-8919-0fa81bcb590a";
var newAddr = url.substr(22,url.length);
// newAddr == "/cooks/cooking-dress-wine/~no-order/pr?p%5B%5D=sort%3Dfeatured&sid=bks%2C43p&mycracker=ch_vn_clothing_subcategory_Puma&ref=b41c8097-8efe-4acf-8919-0fa81bcb590a"
22 is where to start slicing up the string.
url.length is how much of it to include.
This works as long as the domain name remains the same on the links.

Trimming a string from the end in Javascript

In Javascript, how can I trim a string by a number of characters from the end, append another string, and re-append the initially cut-off string again?
In particular, I have filename.png and want to turn it into filename-thumbnail.png.
I am looking for something along the lines of:
var sImage = "filename.png";
var sAppend = "-thumbnail";
var sThumbnail = magicHere(sImage, sAppend);

You can use .slice, which accepts negative indexes:
function insert(str, sub, pos) {
return str.slice(0, pos) + sub + str.slice(pos);
// "filename" + "-thumbnail" + ".png"
}
Usage:
insert("filename.png", "-thumbnail", -4); // insert at 4th from end

Try using a regular expression (Good documentation can be found at https://developer.mozilla.org/en/JavaScript/Guide/Regular_Expressions)
I haven't tested but try something like:
var re = /(.*)\.png$/;
var str = "filename.png";
var newstr = str.replace(re, "$1-thumbnail.png");
console.log(newstr);

I would use a regular expression to find the various parts of the filename and then rearrange and add strings as needed from there.
Something like this:
var file='filename.png';
var re1='((?:[a-z][a-z0-9_]*))';
var re2='.*?';
var re3='((?:[a-z][a-z0-9_]*))';
var p = new RegExp(re1+re2+re3,["i"]);
var m = p.exec(file);
if (m != null) {
var fileName=m[1];
var fileExtension=m[2];
}
That would give you your file's name in fileName and file's extension in fileExtension. From there you could append or prepend anything you want.
var newFile = fileName + '-thumbnail' + '.' + fileExtension;

Perhaps simpler than regular expressions, you could use lastindexof (see http://www.w3schools.com/jsref/jsref_lastindexof.asp) to find the file extension (look for the period - this allows for longer file extensions like .html), then use slice as suggested by pimvdb.

You could use a regular expression and do something like this:
var sImage = "filename.png";
var sAppend = "-thumbnail$1";
var rExtension = /(\.[\w\d]+)$/;
var sThumbnail = sImage.replace(rExtension, sAppend);
rExtension is a regular expression which looks for the extension, capturing it into $1. You'll see that $1 appears inside of sAppend, which means "put the extension here".
EDIT: This solution will work with any file extension of any length. See it in action here: http://jsfiddle.net/h4Qsv/

Remove a query argument from a URL in javascript

I'm trying to write a function that will remove a query argument from a url in javascript. I think I have it using regex, but I'm not sure if I've missed anything. Also, I can't shake the feeling that there was probably a better way to do this that didn't involve me messing around with regex half the day and running the risk of later finding out that I didn't take some kind of corner case into account.
remove_query_argument = function(url, arg){
var query_arg_regex;
// Remove occurences that come after '&' symbols and not the first one after the '?'
query_arg_regex = new RegExp('&' + arg + '=[^(?:&|$)]*', 'ig');
url = url.replace(query_arg_regex, '');
// remove the instance that the argument to remove is the first one
query_arg_regex = new RegExp('[?]' + arg + '[^(?:&|$)]*(&?)', 'i');
url = url.replace(query_arg_regex, function (match, capture) {
if( capture != '&' ){
return '';
}else{
return '?'
}
});
return url;
}
Does anyone see any problems with this code or would like to suggest a better implementation or way of going about this?
Thanks!

If you have a lot of URL-related operations, you better try this awesome js library https://github.com/medialize/URI.js

Given a percent-encoded URL, the following function will remove field-value pairs from its query string:
var removeQueryFields = function (url) {
var fields = [].slice.call(arguments, 1).join('|'),
parts = url.split( new RegExp('[&?](' + fields + ')=[^&]*') ),
length = parts.length - 1;
return parts[0] + '?' + (length ? parts[length].slice(1) : '');
}
Some examples:
var string = 'http://server/path/program?f1=v1&f2=v2';
removeQueryFields( string, 'f1' ); // 'http://server/path/program?f2=v2'
removeQueryFields( string, 'f2' ); // 'http://server/path/program?f1=v1'
removeQueryFields( string, 'f1', 'f2' ); // 'http://server/path/program'