Develop Reference

Regular Express for Javascript - Contain a specific word in the beginning after get any character until a certain character comes

I need a certain type of regular expression where I need list of special type of strings from a string. Example input:
str = 'this is extra data which i do not need /type/123456/weqweqweqweqw/ these are more extra data which i dont need /'
Result needed:
/type/123456/weqweqweqweqw/
Here the /type/ string will be constant and the remaining will be dynamic i.e. 123456/weqweqweqweqw and the last string will be /.
I tried:
var myRe = /\/type\/(.*)\//g
But this matches everything from /type/ to the end of the string.

Instead of repeating ., which will match anything, repeat anything but a space via \S+, so that only the URL part of the string will be matched:
const str = 'this is extra data which i do not need /type/123456/weqweqweqweqw/ these are more extra data which i dont need /';
console.log(str.match(/\/type\S+/));

It's tagged Python, so here is a solution:
import re
re.search(r"/type/[^/]*/[^/]*/",str)
Out: <_sre.SRE_Match object; span=(39, 66), match='/type/123456/weqweqweqweqw/'>

string replace using a regex

I have a string after Json.stringify in javascript using node. I wanted to replace the text in the string which starts with 'ab' then followed by some numbers(atleast one digit), with 'ab^^^^^^' where the number of '^' s should be equal to the number of digits after ab. The text starting with ab can occur atleast once, In this example it occurs twice. I need help in regex and replacing the string
string - in this, text starting with ab occurs twice.
var str = JSON.stringify({"abc":{"idcardno":"ertyuiop","form":{"somestring":"This string:\n- can have multiple \nab12345ab5677\n","flag":"true","flag2":"false"},"anothertext":"samplestring","numbetstr":"7"}});
after the regex replace it should be like this
{"abc":{"idcardno":"ertyuiop","form":{"somestring":"This string:\n- can have multiple \na^^^^^ab^^^^\n","flag":"true","flag2":"false"},"anothertext":"samplestring","numbetstr":"7"}}
Edit
As per the post below the below will be the contents of obj.abc.form.string, coming in multiple lines. How do I do the regex(above mentioned) replace of this object?
This string:
- can have multiple
ab12345ab56778

Don't process stringifed JSON with regexp. Process the JavaScript object itself, then stringify. In your case, assuming obj is the input:
obj.abc.form.somestring = transform(obj.abc.form.somestring);
str = JSON.stringify(obj);
where transform is a regexp/replace making the transformation you want.

#torazaburo is right, it's a bad practice to manipulate JSON directly. Once you get ahold of the string in obj.abc.form.somestring, though, you can use replace, passing a function:
str.replace(/ab\d+/g, function(match) {return match.replace(/\d/g,'^')})

Splitting string with javascript using '>' character

I acknowledge that this question has probably been asked so many times before and I have tried searching all over StackOverflow for a solution, but so far nothing has worked for me.
I want to split a string but it's not working properly and spitting out individual characters as each item in an array. The string I have from my CMS uses ">" characters to separate and I am using regEx to replace the 'greater than' symbol - with a comma, which works. Sourced this solution from Regex that detects greater than ">" and less than "<" in a string
However, the arrays remain incorrectly formed, like the split() function does not even work:
var myString = "TEST Public Libraries Connect > News Blog > A new item"
var regEx = /<|>/g;
var myNewString = (myString.replace(regEx,","))
alert(myNewString);
myNewString.split(",");
alert(myNewString[0]);
alert(myNewString[1]);
alert(myNewString[2]);
I've put it up in a Fiddle as well, just confused as to why the split won't work properly. Is it because there is spaces in the string?

This should work:
var myNewString = myString.split(">");
https://jsfiddle.net/2j56cva0/3/
In your fiddle, you were splitting myNewString instead of the actual string.

myNewString.split(",");
You need to assign the result of the split to something. It does not just change the string itself into an array.
var parts = myNewString.split(",");

Using regex to split double hyphen but not single hyphen

I have an html element id that looks like this:
dp__1-2--1-3
I'm trying to use the JavaScript split() function to lop off and return the final '1-3'
My regex skills are poor but a bit of searching around got me to this point:
var myId = "dp__1-2--1-3";
var myIdPostFix = myId.split(/[\-\-]+/).pop();
Unfortunately that returns me only the '3'.
So my question is how do I split double hyphens but NOT single hyphens?

It's the brackets in the regular expression that keeps it from working. A set will match one of any of the characers in it, so [\-\-] is the same as [\-], i.e. matching a single hyphen.
Just remove the brackets:
var myIdPostFix = myId.split(/--/).pop();
or just use the string '--' instead of a regular expression:
var myIdPostFix = myId.split('--').pop();

split accepts a regular expression or a string as the first argument.
You were very close. You can achieve what you want with:
var myIdPostFix = myId.split("--").pop();

Javascript:Replace single characters after the string

I'm trying to do something which seems fairly basic, but can't seem to get it working.
I'm trying to strip the characters after the last instance of an underscore.
I have this long Query String:
json_data=demo_title=Demo+title&proc1_script=script.sh+parameters&proc1_chk_make=on&outputp2_value=&demo_input_description=hola+mundo&outputp4_visible=on&outputp4_info=&inputdata1_max_pixels=1024000&tag=&outputp1_id=nanana&proc1_src_compresion=zip&proc1_chk_cmake=off&outputp3_description=&outputp3_value=&inputdata1_description=input+data+description&inputp2_description=bien%3F&inputp3_description=funciona&proc1_cmake=-D+CMAKE_BUILD_TYPE%3Astring%3DRelease+&outputp2_visible=on&outputp3_visible=on&outputp1_type=header&inputp1_type=text&demo_params_description=va+bien&outputp1_description=&inputdata1_type=image2d&proc1_chk_script=off&demo_result_description=win%3F&outputp2_id=nanfdsvfa&inputp1_description=funciona&demo_wait_description=boh&outputp4_description=&inputp2_type=integer&inputp2_id=papapa&outputp1_value=&outputp3_id=nananartrtrt&inputp3_id=pepepe&outputp3_type=header&inputp3_visible=+off&outputp1_visible=on&inputdata1_id=id_lsd&outputp4_value=&inputp2_visible=on&proc1_source=lsd-1.5.zip&inputp3_value=si&proc1_make=-j4+-C+&images_config_file=cfgmydemo.cfg&outputp2_type=header&proc1_subdir=xxx-1.5&proc1_url=http%3A%2F%2Fwww.ipol.im%2Fpub%2Falgo%2F...&inputdata1_image_depth=1x8i&inputp1_id=popopo&inputp1_value=si&inputp2_value=no&demo_data_filename=data_saved.cfg&inputdata1_info=info_lsd&outputp3_info=&inputdata1_image_format=.pgm&outputp1_info=&inputdata1_compress=False&inputp1_visible=on&proc1_id=lsd&outputp4_id=nana&outputp2_description=&outputp4_type=header&outputp2_info=&inputp3_type=float&&tag&inputp4_iddcksmdclk&inputp4_typetext&inputp4_descriptionkldmsclk&inputp4_valueklcdmkl&inputp4_infoclkdmscdl
Now I replace the separator = in separator %24+ and & in +%23+ using fr=fr.replace(/\&/g,"+%23+");
Separator
javascript Mako
= %24+
& +%23+
But the result is:
json_data%24+demo_title%24+Demo+title+%23+proc1_script%24+script.sh+parameters+%23+proc1_chk_make%24+on+%23+outputp2_value%24++%23+demo_input_description%24+hola+mundo+%23+outputp4_visible%24+on+%23+outputp4_info%24++%23+inputdata1_max_pixels%24+1024000+%23+tag%24++%23+outputp1_id%24+nanana+%23+proc1_src_compresion%24+zip+%23+proc1_chk_cmake%24+off+%23+outputp3_description%24++%23+outputp3_value%24++%23+inputdata1_description%24+input+data+description+%23+inputp2_description%24+bien%3F+%23+inputp3_description%24+funciona+%23+proc1_cmake%24+-D+CMAKE_BUILD_TYPE%3Astring%3DRelease++%23+outputp2_visible%24+on+%23+outputp3_visible%24+on+%23+outputp1_type%24+header+%23+inputp1_type%24+text+%23+demo_params_description%24+va+bien+%23+outputp1_description%24++%23+inputdata1_type%24+image2d+%23+proc1_chk_script%24+off+%23+demo_result_description%24+win%3F+%23+outputp2_id%24+nanfdsvfa+%23+inputp1_description%24+funciona+%23+demo_wait_description%24+boh+%23+outputp4_description%24++%23+inputp2_type%24+integer+%23+inputp2_id%24+papapa+%23+outputp1_value%24++%23+outputp3_id%24+nananartrtrt+%23+inputp3_id%24+pepepe+%23+outputp3_type%24+header+%23+inputp3_visible%24++off+%23+outputp1_visible%24+on+%23+inputdata1_id%24+id_lsd+%23+outputp4_value%24++%23+inputp2_visible%24+on+%23+proc1_source%24+lsd-1.5.zip+%23+inputp3_value%24+si+%23+proc1_make%24+-j4+-C++%23+images_config_file%24+cfgmydemo.cfg+%23+outputp2_type%24+header+%23+proc1_subdir%24+xxx-1.5+%23+proc1_url%24+http%3A%2F%2Fwww.ipol.im%2Fpub%2Falgo%2F...+%23+inputdata1_image_depth%24+1x8i+%23+inputp1_id%24+popopo+%23+inputp1_value%24+si+%23+inputp2_value%24+no+%23+demo_data_filename%24+data_saved.cfg+%23+inputdata1_info%24+info_lsd+%23+outputp3_info%24++%23+inputdata1_image_format%24+.pgm+%23+outputp1_info%24++%23+inputdata1_compress%24+False+%23+inputp1_visible%24+on+%23+proc1_id%24+lsd+%23+outputp4_id%24+nana+%23+outputp2_description%24++%23+outputp4_type%24+header+%23+outputp2_info%24++%23+inputp3_type%24+float+%23++%23+tag+%23+inputp4_iddcksmdclk+%23+inputp4_typetext+%23+inputp4_descriptionkldmsclk+%23+inputp4_valueklcdmkl+%23+inputp4_infoclkdmscdl
Now I am interested how to replace this = after the value jsondata.
Explain:
In the Query string there is the string json_data+%23+ and this +%23+ I want replace to =
How?

Strip the characters after the last instance of an underscore:
json_data.substring(0, json_data.lastIndexOf("_"));
Replace +%23+ with =
json_data.replace("+%23+", "=");
However, if you're trying to turn all the %xx into what they're supposed to be, you should url decode the string instead.
Which would probably have to be something like:
decodeURIComponent((json_data).replace('+', '%20'));