Ignore Pattern Whitespace); Validates the format, type, and length of the supplied input field.The input must consist of 3 numeric characters followed by a dash, then 2 numeric characters followed by a dash, and then 4 numeric characters. This content is outdated and is no longer being maintained.To validate other forms of input, such as query strings, cookies, and HTML control input, you can use the System. The attacker can then supply carefully crafted input that compromises your application by attempting SQL injection, cross-site scripting, and other injection attacks.To avoid such vulnerability, you should validate text fields (such as names, addresses, tax identification numbers, and so on) and use regular expressions to do the following: Regular expression support is available to ASP. If you capture input by using server controls, you can use the Regular Expression Validator control to validate that input. $_iu S I have added simple network ranges validation, the rules I used are: - valid range 18.104.22.168 - 22.214.171.124, network adresses above and including 126.96.36.199 are reserved addresses - first and last IP address of each class is excluded since they are used as network broadcast addresses since I don't think this is worth implementing completely in a regular expression, a following pass should exclude the Intranet address space: 10.0.0.0 - 10.255.255.255 172.16.0.0 - 1.255 192.168.0.0 - 192.168.255.255 the loopback and the automatic configuration address space: 127.0.0.0 - 127.255.255.255 169.254.0.0 - 169.254.255.255 while the local, multicast and and the reserved address spaces: 0.0.0.0 - 0.255.255.255 (SPECIAL-IPV4-LOCAL-ID-IANA-RESERVED) 188.8.131.52 - 239.255.255 (MCAST-NET) 240.0.0.0 - 255.255.255.255 (SPECIAL-IPV4-FUTURE-USE-IANA-RESERVED) should already be excluded by the above regular expression.
Hi, is a valid URL but the last dot ist usually not written by convention. works in Firefox and IE Just a small comment about brodcast and network address. Ex: If a provider have two class like 184.108.40.206/24 and 220.127.116.11/24, they can combine the two in a classless network: 18.104.22.168/23.
If you omit these markers, an attacker could affix malicious input to the beginning or end of valid content and bypass your filter. To use the Regex class For performance reasons, you should use the static Is Match method where possible to avoid unnecessary object creation.
If you are not using server controls (which means you cannot use the validation controls) or if you need to validate input from sources other than form fields, such as query string parameters or cookies, you can use the Regex class within the System. The following example shows how to use a regular expression to validate a name input through a regular client-side HTML control.
NET applications through the Regular Expression Validator control and the Regex class in the System. You can use regular expressions to restrict the range of valid characters, to strip unwanted characters, and to perform length and format checks.
You can constrain the input format by defining patterns that the input must match.