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How to use Regex to limit user input to numeric fields, with one allowed decimal and one allowed negative symbol in front

I am trying to only allow numeric values, along with a possible negative symbol at the front of the string, and a single decimal, using Regex in JavaScript. This input value will only allow for a possible 10 digits also.
Currently, when a user inputs text, I have this logic that will only allow numbers, negative signs, and decimals. However, I want to limit the number of the negative sign to one, and only allow this at the front of the string. Also, I want to limit the number of decimals to one.
input.slice(0, 10).replace(/[^0-9.\-]/, '');
Can anyone please help me figure this out?

You can do:
input.slice(0, 10).match(/([-]?)([0-9]+)([.]?)([0-9]?)/);

Short n sweet.
/^-?\d{0,10}(\.\d{0,3})?$/
optional negative char. at the start
allows max of 10 digits next
again optional decimal group with at most 3 decimal places
These barriers can be modified accordingly.

Javascript thousand separator on negative and decimal number without leading zeroes

I am making a table that has input with price on every row, so when the user input positive number, or negative number, or decimal number or negative with decimal number, it need to has thousand separator on the number and should not have leading zeroes. I am avoiding library because using library, I need to change so much code, but i am welcome on library with minor fix. There are many stackoverflow's post on thousand separator without leading zeroes, but the post only dealing with one type number like positive or negative number, what I need is a number that is negative and decimal as well. I prefer regular expression so I don't have to change a lot of code.

Regex to validate number between two ranges

how to validate numbers between 0 to 99999.99 using regex?
basically it should accept the values like 0.01, 0000.01, .01 and 9999.99
also it should have only two values after dot(.)
I tried something like the below but it did not work for me.
/^[0-9]{1,5}.[0-9]{2}$/
decimal is optional
Could someone help pls.

The . character has special meaning in a regex, so you need to escape it.
Anyway, let me see if I got the rules straight:
Decimal point is optional
If decimal point not given:
Between 1 and 5 digits
If decimal point is present:
Between 0 and 5 digits before decimal point
Between 1 and 2 digits after decimal point
Since the number of digits depends on the presence of the decimal point, you make the regex have two choices, separated by |.
Choice 1 (no decimal point): [0-9]{1,5}
Choice 2 (decimal point): [0-9]{0,5}\.[0-9]{1,2}
Since you want anchors (^$), you can either put them in both choices, or surround the choice set with parenthesis. To make it non-capturing, use (?:xxx).
Final regex is one of these:
/^[0-9]{1,5}$|^[0-9]{0,5}\.[0-9]{1,2}$/
/^(?:[0-9]{1,5}|[0-9]{0,5}\.[0-9]{1,2})$/
You can see the second one in effect on regex101.

If javascript then below regex would work:
^\d{0,5}(((\.){0})|((\.){1}\d{1,2}))$
All the above mentioned cases are satisfying.

Thank you and ^(?:\d{1,5}(?:\.\d{1,2})?|\.\d{1,2})$ is what i was trying to get and this serves my purpose.

Javascript regex:
/^\d{1,5}(\.\d{1,2})?$/
Javascript demo

Regex to allow negative values with maximum of 4 decimal places

I need a little help with changing the following regex to allow negative numbers. It needs to allow decimal numbers of up to a maximum of 4 decimal places, which it already does.
/^\d+(\.\d{1,4})?$/
Can anyone help?
Thanks

Just put -? before the first digit - "optionally match a minus sign"

Add the - in the character class with optional(?)
/^[-+]?\d+(\.\d{1,4})?$/

The following allows for integer numbers (123), integer with 1 to 4 fractional part (123.1234) and only 1 to 4 fractional part (.1234), that's usually accepted as a valid number. All options can be prefixed by plus or minus signs:
/^[-+]?(?:\d+|\d*(?:\.\d{1,4})?)$/
The (?:xxx) construction is preferred to (xxx) when we're not interested to capture the matches, because it requires less resources.

Regular expression that match decimal places

I have this code to test if a value entered in a INPUT is numeric:
$("#price").val().match(/^\d+$/);
I need some help rewriting this function to allow decimal places either with colon or dot meaning for example 230.00 is allowed and 230,00 is allowed too. Also the decimal places could be four or less. Any?

Regex: $("#price").val().match(/^\d+([,\.]\d{1,4})?$/);
Regex n2 with negative values: $("#price").val().match(/^-?\d+([,\.]\d{1,4})?$/);
If you need help parsing values related to some culture in specific, take a loot at this https://github.com/jquery/globalize. It's a library about globalization and localization.
Hope it helps!

$("#price").val().match(/^\d+((\.|,)\d+)?$/);
the above won't limit the number of decimal places to four, though.
By the way, that's a comma and not a "colon"
To match decimal places up to 4 only, use this
$("#price").val().match(/^\d+((\.|,)\d{1,4})?$/);
should match 1 to four numbers after . or ,