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What is the regular expression to be used for the sequence of strings occured?

I have a structure of string, I need a regular expression that only picks up the numbers from the structure, and also the expression should report if the structure deviates from the mentioned rule (suppose if I missed any comma or full stop or braces etc)
The structure is - {'telugu':['69492','69493','69494'],'kannada':['72224']}
The regular expression I've tried is /\[(.*?)\]/g;
The above expression is working fine for picking only numbers from the given input, but it's not reporting for the missing of any comma, fullstop or braces etc.
var contentids = {'telugu':['69492','69493','69494'],'kannada':['72224']};
var pattern = /\[(.*?)\]/g;
while ((match = pattern.exec(contentids)) != null) {
var arrayContentids2 = new Array();
arrayContentids2 = match[1].split(",");
}
I am fetching only the numbers from the given input,but I need a validation of missing commas, fullstop, braces etc from the input.

To get all the numbers you can use a RegEx like this /\'(\d+)\'|\"(\d+)\"/g. The second part is only for numbers inside " instead of ', so you can remove this if you want.
To check the balance of braces i would use a simple counting loop and move through the input. I don't think that RegEx are the right tool for this job.
To search missing commas you could use the RegEx /([\'\"]\s*[\'\"])/g and /([\[\(\{]\d+)/g to find the tow errors in
{'telugu':['69492','69493','69494'],'kannada':[72224''72224']}
Hope this will help you

regex for serial number in javascript

var serialNumber = $('#SerialNumber').val();
var serialNumberPattern = new RegExp('^[\s\da-zA-z\-.]+$');
if (!serialNumberPattern.test(serialNumber)) {
}
Above is the code I am using to validate a serial number which has alphanumeric characters, dots (.), dashes (-), and slashes (/) in it but somehow it's not working. Where am I going wrong? Please help.

When you're passing regex to RegExp constructor which uses " as regex delimiter, you have to escape all the backslashes one more time. Or otherwise it would be treated as an escape sequence.
var serialNumberPattern = new RegExp("^[\\s\\da-zA-Z.-]+$");
alphanumeric,dot(.),Dash(-),Slash(/) in it.
var serialNumberPattern = new RegExp("^[\\da-zA-Z./-]+$");

Just use /^[\s\da-zA-Z\-.\/]+$/, it's simple and works just fine.
You should only use the RegExp constructor when parts of the expression use a variable. This is not true in your case and just adds additional confusion.
document.write(/^[\s\da-zA-Z\-.\/]+$/.test('23 43-89'))

javascript regex to require at least one special character

I've seen plenty of regex examples that will not allow any special characters. I need one that requires at least one special character.
I'm looking at a C# regex
var regexItem = new Regex("^[a-zA-Z0-9 ]*$");
Can this be converted to use with javascript? Do I need to escape any of the characters?
Based an example I have built this so far:
var regex = "^[a-zA-Z0-9 ]*$";
//Must have one special character
if (regex.exec(resetPassword)) {
isValid = false;
$('#vsResetPassword').append('Password must contain at least 1 special character.');
}
Can someone please identify my error, or guide me down a more efficient path? The error I'm currently getting is that regex has no 'exec' method

Your problem is that "^[a-zA-Z0-9 ]*$" is a string, and you need a regex:
var regex = /^[a-zA-Z0-9 ]*$/; // one way
var regex = new RegExp("^[a-zA-Z0-9 ]*$"); // another way
[more information]
Other than that, your code looks fine.

In javascript, regexs are formatted like this:
/^[a-zA-Z0-9 ]*$/
Note that there are no quotation marks and instead you use forward slashes at the beginning and end.

In javascript, you can create a regular expression object two ways.
1) You can use the constructor method with the RegExp object (note the different spelling than what you were using):
var regexItem = new RegExp("^[a-zA-Z0-9 ]*$");
2) You can use the literal syntax built into the language:
var regexItem = /^[a-zA-Z0-9 ]*$/;
The advantage of the second is that you only have to escape a forward slash, you don't have to worry about quotes. The advantage of the first is that you can programmatically construct a string from various parts and then pass it to the RegExp constructor.
Further, the optional flags for the regular expression are passed like this in the two forms:
var regexItem = new RegExp("^[A-Z0-9 ]*$", "i");
var regexItem = /^[A-Z0-9 ]*$/i;
In javascript, it seems to be a more common convention to the user /regex/ method that is built into the parser unless you are dynamically constructing a string or the flags.

Regex to match carriage return in Javascript

I am trying to write some Javascript to hide some elements that contain only carriage returns. I appreciate that the correct way to solve this problem would be to stop these elements being created, but unfortunately that is not possible in this instance. I am trying to user a regular expression to search for the unwanted elements but am not having much luck. The function I have written is as follows:
function HideEmptyP()
{
var patt = (\\r)
for(var i = 0;i<desc[i].length;i++);
{
var desc[i] = document.getElementsByClassName('sitspagedesc');
var result[i] = patt.test(desc[i]);
if (result[i] == true)
{
desc[i].style.display='none';
}
else
{
alert("No Match!");
}
}
The error I'm getting in the Web Console is 'Syntax Error: Illegal Character'.
Grateful for any ideas on how to solve this.
Thanks in advance.

I am trying to write some Javascript to hide some elements that contain only carriage returns.
There's no need for a regular expression for that, just compare the element's innerHTML property to "\\r", e.g.:
if (demo[i].innerHTML === "\\r") {
// Remove it
}
But beware that some browsers may transform a single carriage return. You might want to check for "\\r", "\\n", and just a space. To do that, you might want to use a regular expression.
Your regular expression literal ((\\r)) is just completely invalid, it's worth reading up on them to learn the correct syntax. To write a regular expression literal in JavaScript, you use / as the delimiter. So: /\\r/. To test that a string contains only \r, \n, or space, you can use /^[\r\n ]+$/ (which requires there be at least one character that matches, and uses ^ to indicate start-of-string, and $ to indicate end-of-string):
if (demo[i].innerHTML.match(/^[\r\n ]+$/) {
// Remove it
}

The reason you are getting Syntax error is because the declaration
var patt = (\r)
is incorrect it should be somethign like var patt = '\r';
Also the whole for loop is wrong.
You should define demo before you start the for loop not inside it, and result need not be an array but just a normal variable

Your litteral seems odd.
Try var patt = /\r/;

var patt=/\n/gi
should work.
extra i flag to denote case insensitive.
g for global search.

Javascript Regex after specific string

I have several Javascript strings (using jQuery). All of them follow the same pattern, starting with 'ajax-', and ending with a name. For instance 'ajax-first', 'ajax-last', 'ajax-email', etc.
How can I make a regex to only grab the string after 'ajax-'?
So instead of 'ajax-email', I want just 'email'.

You don't need RegEx for this. If your prefix is always "ajax-" then you just can do this:
var name = string.substring(5);

Given a comment you made on another user's post, try the following:
var $li = jQuery(this).parents('li').get(0);
var ajaxName = $li.className.match(/(?:^|\s)ajax-(.*?)(?:$|\s)/)[1];
Demo can be found here
Below kept for reference only
var ajaxName = 'ajax-first'.match(/(\w+)$/)[0];
alert(ajaxName);
Use the \w (word) pattern and bind it to the end of the string. This will force a grab of everything past the last hyphen (assuming the value consists of only [upper/lower]case letters, numbers or an underscore).
The non-regex approach could also use the String.split method, coupled with Array.pop.
var parts = 'ajax-first'.split('-');
var ajaxName = parts.pop();
alert(ajaxName);

you can try to replace ajax- with ""

I like the split method #Brad Christie mentions, but I would just do
function getLastPart(str,delimiter) {
return str.split(delimiter)[1];
}
This works if you will always have only two-part strings separated by a hyphen. If you wanted to generalize it for any particular piece of a multiple-hyphenated string, you would need to write a more involved function that included an index, but then you'd have to check for out of bounds errors, etc.