i have a problem i'm trying to solve, i have a javascript string (yes this is the string i have)
<div class="stories-title" onclick="fun(4,'this is test'); navigate(1)
What i want to achieve are the following points:
1) cut characters from start until the first ' character (cut the ' too)
2) cut characters from second ' character until the end of the string
3) put what's remaining in a variable
For example, the result of this example would be the string "this is test"
I would be very grateful if anyone have a solution.. Especially a simple one so i can understand it.
Thanks all in advance
You can use split() function:
var mystr = str.split("'")[1];
var newstr = str.replace(/[^']+'([^']+).*/,'$1');
No need to cut anything, you just want to match the string between the first ' and the second ' - see similar questions like Javascript RegExp to find all occurences of a a quoted word in an array
var string = "<div class=\"stories-title\" onclick=\"fun(4,'this is test'); navigate(1)";
var m = string.match(/'(.+?)'/);
if (m)
return m[1]; // the matching group
You can use regular expressions
/\'(.+)\'/
http://rubular.com/r/RcVmejJOmU
http://www.regular-expressions.info/javascript.html
If you want to do the work yourself:
var str = "<div class=\"stories-title\" onclick=\"fun(4,'this is test'); navigate(1)";
var newstr = "";
for (var i = 0; i < str.length; i++) {
if (str[i] == '\'') {
while (str[++i] != '\'') {
newstr += str[i];
}
break;
}
}
Related
Hey guys i am currently learning javascript, i need to replace "-" with "_".
For example : "Hello-World" ==> "Hello_World" i tired the below code it didn't work,i want to know why this method is wrong,
function kS(n){
j=n.length;
for(i=0;i<j;i++){
if(n[i]=="-")
{
n[i]="_";
console.log(n);
}
}
}
Simply use replace
console.log("Hello-World".replace('-','_'))
You can just use String.replace to achieve that. If you use the regex input in combination with g modifier, it will match all occurences. https://regex101.com/ is a good place to test out such regexes.
var myString = "hello-word";
myString = myString.replace(/-/g, '_');
If you have to do it with a loop and are allowed to use ES2015 or newer, you could also write it like this:
var myString = "hello-word";
var newString = [...myString].map(c => c === '-' ? '_' : c).join('');
Stings are immutable. You could convert the string to an array of characters and check and replace the item in the characters array.
At the end return a joined array.
BTW, spelling matter, eg length and undeclared variables are global in Javascript, which should be avoided.
function kS([...characters]) {
var l = characters.length;
for (var i = 0; i < l; i++) {
if (characters[i] === "-") characters[i] = "_";
}
return characters.join('');
}
console.log(kS('1-2-3'));
So as the title says I'd like to add to every character of a string a backslash, whether the string has special characters or not. The string should not be considered 'safe'
eg:
let str = 'dj%^3&something';
str = str.replace(x, y);
// str = '\d\j\%\^\3\&\s\o\m\e\t\h\i\n\g'
You could capture every character in the string with (.) and use \\$1 as replacement, I'm not an expert but basically \\ will render to \ and $1 will render to whatever (.) captures.
HIH
EDIT
please refer to Wiktor Stribiżew's comment for an alternative which will require less coding. Changes as follows:
str = str.replace(/(.)/g, '\\$1'); for str = str.replace(/./g, '\\$&');
Also, for future reference I strongly advice you to visit regexr.com when it comes to regular expressions, it's helped ME a lot
let str = 'dj%^3&something';
str = str.replace(/(.)/g, '\\$1');
console.log(str);
If you just want to display a string safely, you should just do:
let str = 'dj%^3&something';
let node = document.createTextNode(str);
let dest = document.querySelector('.whatever');
dest.appendChild(node);
And then you are guaranteed that it will be treated as text, and won't be able to execute a script or anything.
For example: https://jsfiddle.net/s6udj03L/1/
You can split the string to an array, add a \ to each element to the array, then joint the array back to the string that you wanted.
var str = 'dj%^3&something';
var split = str.split(""); // split string into array
for (var i = 0; i < split.length; i++) {
split[i] = '\\' + split[i]; // add backslash to each element in array
}
var joint = split.join('') // joint array to string
console.log(joint);
If you don't care about creating a new string and don't really have to use a regex, why not just iterate over the existing one and place a \ before each char. Notice to you have to put \\ to escape the first \.
To consider it safe, you have to encode it somehow. You could replace typical 'non-safe' characters like in the encode() function below. Notice how & get's replaced by &
let str = 'dj%^3&something';
let out = "";
for(var i = 0; i < str.length; i++) {
out += ("\\" + str[i]);
}
console.log(out);
console.log(encode(out));
function encode(string) {
return String(string).replace(/&/g, '&').replace(/</g, '<').replace(/>/g, '>').replace(/"/g, '"');
}
base on the following string
...here..
..there...
.their.here.
How can i remove the . on the beginning and end of string like the trim that removes all spaces, using javascript
the output should be
here
there
their.here
These are the reasons why the RegEx for this task is /(^\.+|\.+$)/mg:
Inside /()/ is where you write the pattern of the substring you want to find in the string:
/(ol)/ This will find the substring ol in the string.
var x = "colt".replace(/(ol)/, 'a'); will give you x == "cat";
The ^\.+|\.+$ in /()/ is separated into 2 parts by the symbol | [means or]
^\.+ and \.+$
^\.+ means to find as many . as possible at the start.
^ means at the start; \ is to escape the character; adding + behind a character means to match any string containing one or more that character
\.+$ means to find as many . as possible at the end.
$ means at the end.
The m behind /()/ is used to specify that if the string has newline or carriage return characters, the ^ and $ operators will now match against a newline boundary, instead of a string boundary.
The g behind /()/ is used to perform a global match: so it find all matches rather than stopping after the first match.
To learn more about RegEx you can check out this guide.
Try to use the following regex
var text = '...here..\n..there...\n.their.here.';
var replaced = text.replace(/(^\.+|\.+$)/mg, '');
Here is working Demo
Use Regex /(^\.+|\.+$)/mg
^ represent at start
\.+ one or many full stops
$ represents at end
so:
var text = '...here..\n..there...\n.their.here.';
alert(text.replace(/(^\.+|\.+$)/mg, ''));
Here is an non regular expression answer which utilizes String.prototype
String.prototype.strim = function(needle){
var first_pos = 0;
var last_pos = this.length-1;
//find first non needle char position
for(var i = 0; i<this.length;i++){
if(this.charAt(i) !== needle){
first_pos = (i == 0? 0:i);
break;
}
}
//find last non needle char position
for(var i = this.length-1; i>0;i--){
if(this.charAt(i) !== needle){
last_pos = (i == this.length? this.length:i+1);
break;
}
}
return this.substring(first_pos,last_pos);
}
alert("...here..".strim('.'));
alert("..there...".strim('.'))
alert(".their.here.".strim('.'))
alert("hereagain..".strim('.'))
and see it working here : http://jsfiddle.net/cettox/VQPbp/
Slightly more code-golfy, if not readable, non-regexp prototype extension:
String.prototype.strim = function(needle) {
var out = this;
while (0 === out.indexOf(needle))
out = out.substr(needle.length);
while (out.length === out.lastIndexOf(needle) + needle.length)
out = out.slice(0,out.length-needle.length);
return out;
}
var spam = "this is a string that ends with thisthis";
alert("#" + spam.strim("this") + "#");
Fiddle-ige
Use RegEx with javaScript Replace
var res = s.replace(/(^\.+|\.+$)/mg, '');
We can use replace() method to remove the unwanted string in a string
Example:
var str = '<pre>I'm big fan of Stackoverflow</pre>'
str.replace(/<pre>/g, '').replace(/<\/pre>/g, '')
console.log(str)
output:
Check rules on RULES blotter
What function will turn this contains spaces into this contains spaces using javascript?
I've tried the following, using similar SO questions, but could not get this to work.
var string = " this contains spaces ";
newString = string.replace(/\s+/g,''); // "thiscontainsspaces"
newString = string.replace(/ +/g,''); //"thiscontainsspaces"
Is there a simple pure javascript way to accomplish this?
You're close.
Remember that replace replaces the found text with the second argument. So:
newString = string.replace(/\s+/g,''); // "thiscontainsspaces"
Finds any number of sequential spaces and removes them. Try replacing them with a single space instead!
newString = string.replace(/\s+/g,' ').trim();
string.replace(/\s+/g, ' ').trim()
Try this one, this will replace 2 or 2+ white spaces from string.
const string = " this contains spaces ";
string.replace(/\s{2,}/g, ' ').trim()
Output
this contains spaces
I figured out one way, but am curious if there is a better way...
string.replace(/\s+/g,' ').trim()
I got the same problem and I fixed like this
Text = Text.replace(/ {1,}/g," ");
Text = Text.trim();
I think images always explain it's good, basically what you see that the regex \s meaning in regex is whitespace. the + says it's can be multiply times. /g symbol that it's looks globally (replace by default looks for the first occur without the /g added). and the trim will remove the last and first whitespaces if exists.
Finally, To remove extra whitespaces you will need this code:
newString = string.replace(/\s+/g,' ').trim();
We can use the below approach to remove extra space in a sentence/word.
sentence.split(' ').filter(word => word).join(' ')
Raw Javascript Solution:
var str = ' k g alok deshwal';
function removeMoreThanOneSpace() {
String.prototype.removeSpaceByLength=function(index, length) {
console.log("in remove", this.substr(0, index));
return this.substr(0, index) + this.substr(length);
}
for(let i = 0; i < str.length-1; i++) {
if(str[i] === " " && str[i+1] === " ") {
str = str.removeSpaceByLength(i, i+1);
i = i-1;
}
}
return str;
}
console.log(removeMoreThanOneSpace(str));
var s=" i am a student "
var r='';
console.log(s);
var i,j;
j=0;
for(k=0; s[k]!=undefined; k++);// to calculate the length of a string
for(i=0;i<k;i++){
if(s[i]!==' '){
for(;s[i]!==' ';i++){
r+=s[i];
}
r+=' ';
}
}
console.log(r);
// Here my solution
const trimString = value => {
const allStringElementsToArray = value.split('');
// transform "abcd efgh" to ['a', 'b', 'c', 'd',' ','e', 'f','g','h']
const allElementsSanitized = allStringElementsToArray.map(e => e.trim());
// Remove all blank spaces from array
const finalValue = allElementsSanitized.join('');
// Transform the sanitized array ['a','b','c','d','e','f','g','h'] to 'abcdefgh'
return finalValue;
}
I have tried regex to solve this problem :
let temp=text.replace(/\s{2,}/g, ' ').trim()
console.log(temp);
input="Plese complete your work on Time"
output="Please complete your work on Time"
//This code remove extra spaces with out using "string objectives"
s=" This Is Working On Functions "
console.log(s)
final="";
res='';
function result(s) {
for(var i=0;i<s.length;i++)
{
if(!(final==""&&s[i]==" ")&&!(s[i]===" "&& s[i+1] ===" ")){
final+=s[i];
}
}
console.log(final);
}
result(s);
How to globally replace a forward slash in a JavaScript string?
The following would do but only will replace one occurence:
"string".replace('/', 'ForwardSlash');
For a global replacement, or if you prefer regular expressions, you just have to escape the slash:
"string".replace(/\//g, 'ForwardSlash');
Use a regex literal with the g modifier, and escape the forward slash with a backslash so it doesn't clash with the delimiters.
var str = 'some // slashes', replacement = '';
var replaced = str.replace(/\//g, replacement);
You need to wrap the forward slash to avoid cross browser issues or //commenting out.
str = 'this/that and/if';
var newstr = str.replace(/[/]/g, 'ForwardSlash');
Without using regex (though I would only do this if the search string is user input):
var str = 'Hello/ world/ this has two slashes!';
alert(str.split('/').join(',')); // alerts 'Hello, world, this has two slashes!'
Is this what you want?
'string with / in it'.replace(/\//g, '\\');
This has worked for me in turning "//" into just "/".
str.replace(/\/\//g, '/');
Hi a small correction in the above script..
above script skipping the first character when displaying the output.
function stripSlashes(x)
{
var y = "";
for(i = 0; i < x.length; i++)
{
if(x.charAt(i) == "/")
{
y += "";
}
else
{
y+= x.charAt(i);
}
}
return y;
}
This is Christopher Lincolns idea but with correct code:
function replace(str,find,replace){
if (find){
str = str.toString();
var aStr = str.split(find);
for(var i = 0; i < aStr.length; i++) {
if (i > 0){
str = str + replace + aStr[i];
}else{
str = aStr[i];
}
}
}
return str;
}
Example Usage:
var somevariable = replace('//\\\/\/sdfas/\/\/\\\////','\/sdf','replacethis\');
Javascript global string replacement is unecessarily complicated. This function solves that problem. There is probably a small performance impact, but I'm sure its negligable.
Heres an alternative function, looks much cleaner, but is on average about 25 to 20 percent slower than the above function:
function replace(str,find,replace){
if (find){
str = str.toString().split(find).join(replace);
}
return str;
}
var str = '/questions'; // input: "/questions"
while(str.indexOf('/') != -1){
str = str.replace('/', 'http://stackoverflow.com/');
}
alert(str); // output: "http://stackoverflow.com/questions"
The proposed regex /\//g did not work for me; the rest of the line (//g, replacement);) was commented out.
You can create a RegExp object to make it a bit more readable
str.replace(new RegExp('/'), 'foobar');
If you want to replace all of them add the "g" flag
str.replace(new RegExp('/', 'g'), 'foobar');