We Keep Coding

Replace character of a string with the character from an array

I'm trying to make a script that changes text into these cool looking letters, it looks like everything should be working but when I try to send the replaced message it gives me a character like a white question mark on a black background. This: �
Here's the code:
var mm = "test";
var alphabet = "🇦🇧🇨🇩🇪🇫🇬🇭🇮🇯🇰🇱🇲🇳🇴🇵🇶🇷🇸🇹🇺🇻🇼🇽🇾🇿";
var nalphabet = "abcdefghijklmnopqrstuvwxyz";
for(var z in mm){
var x = nalphabet.indexOf(mm[z].toLowerCase());
var ool = alphabet[x];
msg.channel.sendMessage(ool);
}

This is all about the coding of characters. Each of your cool-looking letters has length 2. So when you try to get such character directly by index, you receive just a half of it. As a solution you can try to join two sibling characters. Something like this
var mm = "test";
var alphabet = "🇦🇧🇨🇩🇪🇫🇬🇭🇮🇯🇰🇱🇲🇳🇴🇵🇶🇷🇸🇹🇺🇻🇼🇽🇾🇿";
var nalphabet = "abcdefghijklmnopqrstuvwxyz";
for(var z in mm){
var x = nalphabet.indexOf(mm[z].toLowerCase());
var ool = alphabet[x * 2] + alphabet[x * 2 + 1];
msg.channel.sendMessage(ool);
}

Try this one:
var message = "test";
var alphabet = ["🇦","🇧","🇨","🇩","🇪",
"🇫","🇬","🇭","🇮","🇯",
"🇰","🇱","🇲","🇳","🇴",
"🇵","🇶","🇷","🇸","🇹",
"🇺","🇻","🇼","🇽","🇾","🇿"];
var nalphabet = "abcdefghijklmnopqrstuvwxyz";
for(var letter in message) {
var x = nalphabet.indexOf(message[letter].toLowerCase());
var ool = alphabet[x];
document.write(ool);
}
Here is a Fiddle.

Javascript-split() not working when there are repeated chars in a string

Not sure how valid is this approach, but I'm unable to split the string into 2 when there are repeated characters.
var match = 's';
var str = "message";
var res = str.split(match, 2);
For instance i tried to use split() on the string "message", it results into:
me,""
So i did this:
res = str.split(match, 3);
so now it resulted into:
me,,age
but as you can see im still missing the second 's' in the "message" string. what im trying to get is I'm passing a matched character (in above case var match which is dynamically generated) to the split() and splitting into 2. I was hoping to get something this:
res = me,,sage
is that possible using split() or is there a better method to achieve this?
P.S: in fiddle i've given another string eg: (string = "shadow") which works fine.
Fails only when there are repeated letters in the string!
fiddle: https://jsfiddle.net/ukeeq656/
EDIT::::::::::::
Thanks everyone for helping me out on this...and so sorry for last min update on the input, i just realized that var match; could be a word too, as in var match = 'force'; and not just var match ='s'; where the string is "forceProduct", so when my match is more than just a letter, this approach works: str.split(match, 2);, but str.indexOf(match); doesnt obviously... could there be an approach to split: "","Product". My extreme apologies for not mentioning this earlier.any help on this would be appreciated!!
eg fiddle:
https://jsfiddle.net/ukeeq656/3/

I don't think split() is the correct way to do this.
Please see below:
var match = 's';
var str = "message";
var index = str.indexOf(match);
var res =[];
res[0] = str.substring(0, index);
res[1] = " ";
res[2] = str.substring(index + 1);
console.log(res);

I'm not sure what your end goal is but I think this gets you what you want.
var match = 's';
var str = "message";
var index = str.indexOf(match);
var res = str.substring(0, index) + ',' + str.substring(index + 1);
alert(res); // me,sage

You could write a function to do this;
function newSplit(str, match) {
var num = str.indexOf(match);
var res = [];
res.push(str.substring(0, num));
//res.push(str.substring(num + 1, str.length)); // this line has been modified
res.push(str.substring(num + match.length, str.length));
return res;
}
var match = 'force';
var str = 'forceProduct';
console.log(newSplit(str, match));
This is what you want?

JavaScript get character in sting after [ and before ]

I have some strings like:
str1 = "Point[A,B]"
str2 = "Segment[A,B]"
str3 = "Circle[C,D]"
str4 = "Point[Q,L]"
Now I want to have function that gives me character after "[" and the character before "]". How could I make something like that ?

try this one...
var str = "Point[A,B]";
var start_pos = str.indexOf('[') + 1;
var end_pos = str.indexOf(']',start_pos);
var text_to_get = str.substring(start_pos,end_pos)
alert(text_to_get);

You'd need regex to do that
var matches = /\[(.*?)\]/.exec(str1);
alert(matches[1]);

You can use match() to extract the characters:
str.match(/\[(.*)\]/)[1]
A safer way would be:
var matches = str.match(/\[(.*)\]/);
if(matches) {
var chars = matches[1];
}

Here's an approach which avoids regex.
var str = "Point[A,B]";
var afterOpenBracket = str.split("[")[1]; // returns "A,B]"
var bracketContents = afterOpenBracket.split("]")[0]; // returns "A,B"
There, pretty simple! bracketContents now contains the entirety of the text between the first set of brackets.
We can stop here, but I'll go a step further anyway and split up the parameters.
var parameters = bracketContents.split(","); // returns ["A", "B"]

Or in case u have more [A,C,D,B] and don't want to use regex:
var str1 = "Point[A,C,D,B]";
function extract(str1){
var a = str1.charAt(str1.indexOf('[')+1);
var b = str1.charAt(str1.indexOf(']')-1);
return [a, b];
//or
//a.concat(b); //to get a string with that values
}
console.log(extract(str1));

concat variable in regexp pattern

I use this regex
str = "asd34rgr888gfd98";
var p = str.match(/\d{2}/);
alert(p[0]);
butI not understood how can use variable as quantificator, that is how write this:
var number = 2;
var p = str.match(/\d{number}/);
P.S. I see this page JavaScript regex pattern concatenate with variable
but not understood how use example from these posts, in my case.

You need to build your regex as a string and pass it to the RegExp constructor:
var regexString = '\\d{' + number + '}';
var regex = new RegExp(regexString);
var p = str.match(regex);
Notice that when building a regex via a string, you need to add some extra escape characters to escape the string as well as the regex.

var number = "2"
var p = new RegExp("\\d{" + number + "}");

This should work:
var str = "asd34rgr888gfd98";
number = 3;
p = str.match(new RegExp('\\d{' + number + '}'));
alert(p[0]);

Global Replace with js

I have the following string:
[27564][85938][457438][273][48232]
I want to replace all the [ with ''. I tried the following but it didn't work:
var str = '[27564][85938][457438][273][48232]'
var nChar = '[';
var re = new RegExp(nChar, 'g')
var visList = str.replace(re,'');
what am I doing wrong here?
Many thanks in advance.

You need to escape the [ otherwise it is interpreted as the start of a character class:
var nChar = '\\[';
If nChar is a variable (and I assume it is otherwise there would be little point in using RegExp instead of /.../g) then you may find this question useful:
Is there a RegExp.escape function in Javascript?

var string = "[27564][85938][457438][273][48232]";
alert(string.replace(/\[/g, '')); //outputs 27564]85938]457438]273]48232]
I escaped the [ character and used a global flag to replace all instances of the character.

I met this problem today.
The requirement is replace all "c++" in user input string. Because "+" has meaning in Reg expression, string.replace fails.
So I wrote a multi-replace function for js string. Hope this can help.
String.prototype.mreplace = function (o, n) {
var off = 0;
var start = 0;
var ret = "";
while(true){
off = this.indexOf(o, start);
if (off < 0)
{
ret += this.substring(start, this.length);
break;
}
ret += this.substring(start, off) + n;
start = off + o.length;
}
return ret;
}
Example:
"ababc".mreplace("a", "a--"); // returns "a--ba--bc"