Develop Reference

Generate random 6 characters based on input

Generate random 6 characters based on input. Like I want to turn 1028797107357892628 into j4w8p. Or 102879708974181177 into lg36k but I want it to be consistant. Like whenever I feed 1028797107357892628 in, it should always spit out j4w8p. Is this possible? (Without a database if possible.) I know how to generate random 6 characters but I dont know how to connect it with an input tbh. I would appreciate any help, thanks.
let rid = (Math.random() + 1).toString(36).substring(7);

You can create a custom hashing function a simple function to your code would be
const seed = "1028797089741811773";
function customHash(str, outLen){
//The 4 in the next regex needs to be the length of the seed divided by the desired hash lenght
const regx = new RegExp(`.{1,${Math.floor(str.length / outLen)}}`, 'g')
const splitted = str.match(regx);
let out = "";
for(const c of splitted){
let ASCII = c % 126;
if( ASCII < 33) ASCII = 33
out += String.fromCharCode(ASCII)
}
return out.slice(0, outLen)
}
const output = customHash(seed, 6)
console.log(output)

It is called hashing, hashing is not random. In your example to get rid:
let rid = (Math.random() + 1).toString(36).substring(7);
Because it is random, it's impossible to be able to produce "consistant result" as you expect.
You need algorithm to produce a "random" consistant result.

Thanks everyone, solved my issue.
Code:
let seed = Number(1028797089741811773)
let rid = seed.toString(36).substring(0,6)
console.log(rid)
Or:
let seed = Number(1028797089741811773)
let rid = seed.toString(36).substring(6)
console.log(rid)

Javascript extract last numbers from Math.random

So I'm trying to do a script for Photoshop with javascript and I can't get the last 6 number from a Math.random.
I tried using the same code as in Strings with "randomID.substr(randomID.length - 6);" or "randomID.substr(-6);" but that didn't work.
var kodi = 'FJ0B';
var randomID = Math.floor(Math.random() * (999999999999 - 100000000000 + 1) + 100000000000);
var lastSix = randomID.toFixed(-6);
var kontrataLayer = (kodi.charAt(0) + lastSix);
Math.floor works fine, I need it with 12 digits for another function.
Thank you.

What about:
var randomIDString = randomID.toString();
var lastSix = Number(randomIDString.substr(randomIDString.length - 6));
For substr to work you need to convert the number to a string. Maybe that's why it didn't work for you earlier?

How do you divide a string of random letters into pairs of substrings and replace with new characters continuously in Javascript?

So I'm working on this project that involves translating a string of text such as "als;kdfja;lsjkdf" into regular charaters like "the big dog" by parsing for certain pairs of letters that translate. (i.e: "fj" = "D")
The catch is I cant simply use the .replace() function in javascript, because there are many occurences where it's given the text "fjkl", and needs to find "jk" and logically interprets the collision of "fj" and "kl" to say that it's found it. This wont work for me, because for me, it didnt find it, as i am only trying to look at found pairs within 2 characters at a time. (i.e: "fjkl" could only yeild "fj" and "kl".)
(In the end I intend to utilize just the 8 characters "asdfjkl;" and set pairs of characters to actual letters. (in this subsitution method, fyi, "fj" OR "jf" would actually be "_"(space). )
in trying to figure out this task in javascript, (I dont know if another language might handle it more efficiently,) I tried utilizing the "split" function in the following way. (Disclaimer, I'm not sure if this is formatted 100% perfectly)
<textarea id="textbox"></textarea>
<script>
var text = document.getElementById("textbox").value; //getting string from the textarea
var pairs = text.split(/(..)/).filter(String); //spliting string into pairs
if(pairs == "fj"){replace(pairs, " ")} //some sort of subsitution
</script>
Additionally, if possible, i would like the replaced characters to be fed directly into the textarea continuosly as the user types, so the translation happens almost simutaneously. (I'm assuming this will use some sort of setInterval() function?)
If any tips can be given on the correct formatting of which tools i should use in javascript, that would be very outstanding; Thanks in advance.
if your interested, here is full list of subsitutions im making in the end of this project:
syntax:(X OR Y == result)
AJ JA = F
AK KA = V
AL LA = B
A; ;A = Y
SJ JS = N
SK KS = M
SL LS = S
S; ;S = P
DJ JD = A
DK DK = U
DL LD = D
D; ;D = G
FJ JF = _
FK KF = I
FL LF = T
F; ;F = K
AS SA = C
SD DS = L
DF FD = E
JK KJ = O
KL LK = R
L; ;L = Z
AD DA = -
SF FS = ,
AF FA = .
JL LJ = !
K; ;K = :
J; ;J = ?
-Daniel Rehman

I have prepared a code for your requirement. You can bind a function on keydown to allow continuous changes as you type in the textarea.
I am using replacePair method to replace a pair of character by its equivalent uppercase representation. You can inject your own custom logic here.
var tb = document.getElementById('tb');
var processedLength = 0;
var pairEntered=false;
tb.onkeydown = function (e) {
pairEntered=!pairEntered;
if (pairEntered) {
var nextTwoChars = this.value.substr(this.value.length - 2, 2);
var prevPart=this.value.substr(0,this.value.length-2);
var finalText=prevPart+ replacePair(nextTwoChars);
this.value=finalText;
processedLength+=2;
}
}
function replacePair(str){
return str.toUpperCase();
}
jsfiddle:http://jsfiddle.net/218fq7t2/
updated fiddle as per your replacement logic: http://jsfiddle.net/218fq7t2/3/

If you can be assured that certain pairs always translate to the same character, then perhaps a dictionary object can help.
var dict = { as:"A", kl:"B", al:"C", fj:"D" ... };
And, if your 'decryption' algorithm is 'lazy' (evaluates the first pair it encounters), then you can just travel through the input string.
var outputString = "", c, cl;
for (c = 1, cl = inputString.length; c < cl; c += 2) {
outputString += dict[inputString[c-1] + inputString[c]] || "";
}
If your replacement algorithm is not any more complicated than simply looking up which letter the pair represents, then this should do alright for you. No real logic necessary.

Couldn't you do it as follows:
var text = document.getElementById("textbox").value;
for (i = 0; i <= text.length; i++) {
if (text[i] == "j") {
if (text[i+1] == "f") {
pair = "jf";
text = text.replace(pair, "_");
}
}
What this would do is it would always, when checking any letter, also check the letter after it during the same step in the procedure. When it finds both letter i and letter i+1 matching up with a pair you are looking for, then the letters will be replaced by a space (or whatever you want), meaning that when the for-loop reaches the next run after a pair was found, the size of the text string will have been reduced by one. Thus, when it increments i, it will automatically skip the letter that made up the second component of the found pair. Thus, "jfkl" will be identified as two different pairs and your algorithm will not be confused.
of course, you would also have to work in the other pairs/codewords into the for loop so that they are all checked in some way

I had hoped my previous answer was enough to get you started. I was merely providing an algorithm that you could then use to your liking (wrap it in a function and add your own event listeners, etc).
Here is the solution to your problem. I did not write the entire dictionary. You will need to complete that.
var dictionary = { "aj":"F", "ja":"F", "ak":"V", "ka":"V", "al":"B", "la":"B", "a;":"Y", ";a":"Y" }
var input, output;
function init() {
input = document.getElementById("input");
output = document.getElementById("output");
input.addEventListener("keyup", decrypt, false);
}
function decrypt () {
if (!input || !output) {
return;
}
var i = input.value, o = "", c, cl;
for (c = 1, cl = i.length; c < cl; c += 2) {
o += dictionary[ i[c-1] + i[c] ] || "";
}
while (output.hasChildNodes()) {
output.removeChild(output.firstChild);
}
output.appendChild(document.createTextNode(o));
}
window.addEventListener("load", init, false);
<textarea id="input"></textarea>
<div id="output"></div>

Convert comma's into periods js

So I'm trying to make a calculation but it obviously wont calculate with ',' in the numbers. I want to change these vars and make the ',' into '.' using javascript
oldSum.value = '48,35'
newSum.innerHTML = '€43,40'
var oldSumPre = oldSum.value;
var oldStripped = oldSumPre.replace(/,/g, ".");
var newSumPre = newSum.innerHTML;
var newStripped = newSumPre.replace(/,/g, ".");
bedrag.innerHTML = oldStripped - newStripped;
Is what Im doing right now.. but it changes bedrag.innerHTML into NaN

var str = "R,e,p,l,a,c,e";
var res = str.replace(/,/g, ".");
alert (res);

Suppose your variable is vNum. You need to replace all commas with '.' using this
vNum = vNum.replace(",", ".");

In general you could use a localization / internationalization library, which will solve some other tasks you are likely to run into as well.
For example this one:
https://github.com/jquery/globalize/blob/master/doc/api/number/parse-number.md
Snippet:
Globalize.locale( "es" );
Globalize.parseDate( "3,14" ); // 3.14

Javascript RegEx Mysteries (for a poor C programmer)

This is clearly a RTFM issue, but after I did so repeatedly I just can't get the damn thing to work so there are times when asking for help makes sense:
var text = "KEY:01 VAL:1.10,KEY:02 VAL:2.20,KEY:03 VAL:3.30";
var pattern = '/KEY:(\S+) VAL:([^,]+)/g';
//var pattern = '/KEY:(\S+) VAL:(.?+)(?:(?=,KEY:)|$)/g';
//var pattern = '/KEY:(\S+) VAL:(.+)$/g';
//pattern.compile(pattern);
var kv = null;
var row = 0, col = 0;
while((kv = pattern.exec(text) != null))
{
row = kv[1].charAt(0) - '0';
col = kv[1].charAt(1) - '0';
e = document.getElementById('live').rows[row].cells;
e[col].innerHTML = kv[2].slice(0, kv[2].indexOf(","));
}
kv[1] is supposed to give "01"
kv[2] is supposed to give "1.10"
...and of course kv[] should list all the values of 'text'
to fill the table called 'live'.
But I can't get to have pattern.exec() succeed in doing that.
Where is the glitch?

First, the delimiters for the RegExp should be /s, there's no need to put them in ' delimiters. i.e. to get your exec to run properly you should have:
var pattern = /KEY:(\S+) VAL:([^,]+)/g;
Second, you're assigning a boolean to kv which you don't want. The while will obviously only evaluate to true if it's not null so that's redundant. Instead you just need:
while (kv = pattern.exec(text)) {
That should get your code to work as you desire.

the syntax for pattern objects doesn't include quoting, such as:
var pattern=/KEY:(\S+) VAL:([^,]+)/g;
http://www.w3schools.com/jsref/jsref_regexp_exec.asp

It should be
var pattern = /KEY:(\S+) VAL:([^,]+)/g;
http://www.regular-expressions.info/ is a good place to start with.