Hi I want to allow alphanumeric + _ in a text box. but when I press tab it warns me about the special characters are not allowed. Here is the Javascript code. Is there a way to escape tab and carriage return using regular expressions ?
function splChars(str)
{
if (str != "")
{
if (/^[\w _\t\r]+$/.test(str))
return true;
else
return false;
}
}
I think this is what you want:
.replace(/([^a-z0-9_])/gi, '\\$1');
eg:
'abd12^_$'.replace(/([^a-z0-9_])/gi, '\\$1') // "abd12\^_\$"
Related
I want to remove all special characters except space from a string using JavaScript.
For example,
abc's test#s
should output as
abcs tests.
You should use the string replace function, with a single regex.
Assuming by special characters, you mean anything that's not letter, here is a solution:
const str = "abc's test#s";
console.log(str.replace(/[^a-zA-Z ]/g, ""));
You can do it specifying the characters you want to remove:
string = string.replace(/[&\/\\#,+()$~%.'":*?<>{}]/g, '');
Alternatively, to change all characters except numbers and letters, try:
string = string.replace(/[^a-zA-Z0-9]/g, '');
The first solution does not work for any UTF-8 alphabet. (It will cut text such as Привіт). I have managed to create a function which does not use RegExp and use good UTF-8 support in the JavaScript engine. The idea is simple if a symbol is equal in uppercase and lowercase it is a special character. The only exception is made for whitespace.
function removeSpecials(str) {
var lower = str.toLowerCase();
var upper = str.toUpperCase();
var res = "";
for(var i=0; i<lower.length; ++i) {
if(lower[i] != upper[i] || lower[i].trim() === '')
res += str[i];
}
return res;
}
Update: Please note, that this solution works only for languages where there are small and capital letters. In languages like Chinese, this won't work.
Update 2: I came to the original solution when I was working on a fuzzy search. If you also trying to remove special characters to implement search functionality, there is a better approach. Use any transliteration library which will produce you string only from Latin characters and then the simple Regexp will do all magic of removing special characters. (This will work for Chinese also and you also will receive side benefits by making Tromsø == Tromso).
search all not (word characters || space):
str.replace(/[^\w ]/, '')
I don't know JavaScript, but isn't it possible using regex?
Something like [^\w\d\s] will match anything but digits, characters and whitespaces. It would be just a question to find the syntax in JavaScript.
I tried Seagul's very creative solution, but found it treated numbers also as special characters, which did not suit my needs. So here is my (failsafe) tweak of Seagul's solution...
//return true if char is a number
function isNumber (text) {
if(text) {
var reg = new RegExp('[0-9]+$');
return reg.test(text);
}
return false;
}
function removeSpecial (text) {
if(text) {
var lower = text.toLowerCase();
var upper = text.toUpperCase();
var result = "";
for(var i=0; i<lower.length; ++i) {
if(isNumber(text[i]) || (lower[i] != upper[i]) || (lower[i].trim() === '')) {
result += text[i];
}
}
return result;
}
return '';
}
const str = "abc's#thy#^g&test#s";
console.log(str.replace(/[^a-zA-Z ]/g, ""));
Try to use this one
var result= stringToReplace.replace(/[^\w\s]/g, '')
[^] is for negation, \w for [a-zA-Z0-9_] word characters and \s for space,
/[]/g for global
With regular expression
let string = "!#This tool removes $special *characters* /other/ than! digits, characters and spaces!!!$";
var NewString= string.replace(/[^\w\s]/gi, '');
console.log(NewString);
Result //This tool removes special characters other than digits characters and spaces
Live Example : https://helpseotools.com/text-tools/remove-special-characters
dot (.) may not be considered special. I have added an OR condition to Mozfet's & Seagull's answer:
function isNumber (text) {
reg = new RegExp('[0-9]+$');
if(text) {
return reg.test(text);
}
return false;
}
function removeSpecial (text) {
if(text) {
var lower = text.toLowerCase();
var upper = text.toUpperCase();
var result = "";
for(var i=0; i<lower.length; ++i) {
if(isNumber(text[i]) || (lower[i] != upper[i]) || (lower[i].trim() === '') || (lower[i].trim() === '.')) {
result += text[i];
}
}
return result;
}
return '';
}
Try this:
const strippedString = htmlString.replace(/(<([^>]+)>)/gi, "");
console.log(strippedString);
const input = `#if_1 $(PR_CONTRACT_END_DATE) == '23-09-2019' #
Test27919<alerts#imimobile.com> #elseif_1 $(PR_CONTRACT_START_DATE) == '20-09-2019' #
Sender539<rama.sns#gmail.com> #elseif_1 $(PR_ACCOUNT_ID) == '1234' #
AdestraSID<hello#imimobile.co> #else_1#Test27919<alerts#imimobile.com>#endif_1#`;
const replaceString = input.split('$(').join('->').split(')').join('<-');
console.log(replaceString.match(/(?<=->).*?(?=<-)/g));
Whose special characters you want to remove from a string, prepare a list of them and then user javascript replace function to remove all special characters.
var str = 'abc'de#;:sfjkewr47239847duifyh';
alert(str.replace("'","").replace("#","").replace(";","").replace(":",""));
or you can run loop for a whole string and compare single single character with the ASCII code and regenerate a new string.
I want to remove all special characters except space from a string using JavaScript.
For example,
abc's test#s
should output as
abcs tests.
You should use the string replace function, with a single regex.
Assuming by special characters, you mean anything that's not letter, here is a solution:
const str = "abc's test#s";
console.log(str.replace(/[^a-zA-Z ]/g, ""));
You can do it specifying the characters you want to remove:
string = string.replace(/[&\/\\#,+()$~%.'":*?<>{}]/g, '');
Alternatively, to change all characters except numbers and letters, try:
string = string.replace(/[^a-zA-Z0-9]/g, '');
The first solution does not work for any UTF-8 alphabet. (It will cut text such as Привіт). I have managed to create a function which does not use RegExp and use good UTF-8 support in the JavaScript engine. The idea is simple if a symbol is equal in uppercase and lowercase it is a special character. The only exception is made for whitespace.
function removeSpecials(str) {
var lower = str.toLowerCase();
var upper = str.toUpperCase();
var res = "";
for(var i=0; i<lower.length; ++i) {
if(lower[i] != upper[i] || lower[i].trim() === '')
res += str[i];
}
return res;
}
Update: Please note, that this solution works only for languages where there are small and capital letters. In languages like Chinese, this won't work.
Update 2: I came to the original solution when I was working on a fuzzy search. If you also trying to remove special characters to implement search functionality, there is a better approach. Use any transliteration library which will produce you string only from Latin characters and then the simple Regexp will do all magic of removing special characters. (This will work for Chinese also and you also will receive side benefits by making Tromsø == Tromso).
search all not (word characters || space):
str.replace(/[^\w ]/, '')
I don't know JavaScript, but isn't it possible using regex?
Something like [^\w\d\s] will match anything but digits, characters and whitespaces. It would be just a question to find the syntax in JavaScript.
I tried Seagul's very creative solution, but found it treated numbers also as special characters, which did not suit my needs. So here is my (failsafe) tweak of Seagul's solution...
//return true if char is a number
function isNumber (text) {
if(text) {
var reg = new RegExp('[0-9]+$');
return reg.test(text);
}
return false;
}
function removeSpecial (text) {
if(text) {
var lower = text.toLowerCase();
var upper = text.toUpperCase();
var result = "";
for(var i=0; i<lower.length; ++i) {
if(isNumber(text[i]) || (lower[i] != upper[i]) || (lower[i].trim() === '')) {
result += text[i];
}
}
return result;
}
return '';
}
const str = "abc's#thy#^g&test#s";
console.log(str.replace(/[^a-zA-Z ]/g, ""));
Try to use this one
var result= stringToReplace.replace(/[^\w\s]/g, '')
[^] is for negation, \w for [a-zA-Z0-9_] word characters and \s for space,
/[]/g for global
With regular expression
let string = "!#This tool removes $special *characters* /other/ than! digits, characters and spaces!!!$";
var NewString= string.replace(/[^\w\s]/gi, '');
console.log(NewString);
Result //This tool removes special characters other than digits characters and spaces
Live Example : https://helpseotools.com/text-tools/remove-special-characters
dot (.) may not be considered special. I have added an OR condition to Mozfet's & Seagull's answer:
function isNumber (text) {
reg = new RegExp('[0-9]+$');
if(text) {
return reg.test(text);
}
return false;
}
function removeSpecial (text) {
if(text) {
var lower = text.toLowerCase();
var upper = text.toUpperCase();
var result = "";
for(var i=0; i<lower.length; ++i) {
if(isNumber(text[i]) || (lower[i] != upper[i]) || (lower[i].trim() === '') || (lower[i].trim() === '.')) {
result += text[i];
}
}
return result;
}
return '';
}
Try this:
const strippedString = htmlString.replace(/(<([^>]+)>)/gi, "");
console.log(strippedString);
const input = `#if_1 $(PR_CONTRACT_END_DATE) == '23-09-2019' #
Test27919<alerts#imimobile.com> #elseif_1 $(PR_CONTRACT_START_DATE) == '20-09-2019' #
Sender539<rama.sns#gmail.com> #elseif_1 $(PR_ACCOUNT_ID) == '1234' #
AdestraSID<hello#imimobile.co> #else_1#Test27919<alerts#imimobile.com>#endif_1#`;
const replaceString = input.split('$(').join('->').split(')').join('<-');
console.log(replaceString.match(/(?<=->).*?(?=<-)/g));
Whose special characters you want to remove from a string, prepare a list of them and then user javascript replace function to remove all special characters.
var str = 'abc'de#;:sfjkewr47239847duifyh';
alert(str.replace("'","").replace("#","").replace(";","").replace(":",""));
or you can run loop for a whole string and compare single single character with the ASCII code and regenerate a new string.
I need to modify this function to work properly. It is supposed to restrict everything but the alphabet, spaces, and apostrophes. Currently it is still restricting apostrophes. I'm assuming the pattern ' \ _ ' is referring to ALL special characters. How would I insert an exception in to this function?
function NameNotNA (s) {
var pattern;
if (s.toUpperCase().indexOf('N/A') != -1){
//console.warn('failed in n/a');
return false;
}
// Eliminate possibility of digits
pattern = /\d/;
if (s.match(pattern) != null) {
//console.warn('failed in \d');
return false;
}
pattern = /\_/;
if (s.match(pattern) != null) {
//console.warn('failed in \_');
return false;
}
s = s.replace(/ /g, '');
if (s.match(/\W/) != null) {
return false;
}
return true;
}
function nameNotNA (s) {
return s.replace(/[^\w\s']/g, '');
}
For regex, I like using this tool to understand exactly what's happening. Also, it's good to keep your function names lowerCamelCase unless it's a Class.
I know my code is wrong, I am trying to test for certain characters, and as long as they exist for each char in the input field, it will pass true, otherwise pass false.
function isChar(value) {
//Trying to create a regex that allows only Letters, Numbers, and the following special characters # . - ( ) # _
if (!value.toString().match(/#.-()#_$/)) {
return false;
} return true;
}
Assuming you're actually passing a character (you don't show how this is called), this should work:
function isChar(value) {
if (!value.toString().match(/[a-z0-9#.\-()#_\$]/i)) {
return false;
} else
return true;
}
console.log(isChar('%')); // false
console.log(isChar('$')); // true
console.log(isChar('a')); // true
If instead you're passing a string, and wanting to know if all the characters in the string are in this "special" list, you'll want this:
function isChar(value) {
if (! value.match(/^[a-z0-9#.\-()#_\$]*$/i)) {
return false;
} else
return true;
}
console.log(isChar("%$_")); // false
console.log(isChar("a$_")); // true
Characters that have meaning in regexp need to be escaped with \. So for example you would replace $ with \$ and so on for the other such characters. So the final regexp would look like:
#.\-()#_\$
Since you need to escape both the - and the $.
The \w class will catch the alpha numeric. The rest you provided (but properly escaped):
function isChar(value) {
return value.toString().match(/[\w#.\-()#_\$]/) ? true : false
}
how do i extract the part between the brackets in javascript regular expressions:
answer_postal_address[address]
I tried this:
/^\w*/g
which works but i wasn't sure if this was correct...
Matches input of value of any word character followed by anything inside of bracket, i.e. answer_postal_address[address]
var re = new RegExp("\w+\[([^\]]+)\]");
var m = re.exec(input);
if (m == null) {
alert("No match");
}
else {
alert("Matched: " + m[1]);
}
Shouldn't this be sufficient?
Search for: \([.*?]\)
Replace with: $1
So
result = str.replace(/\((.*?)\)/g, "$1");