Commonly used in JavaScript regular expressions to verify

Jul 1 posted in AJAX (RSS), comments.

The correct format: "01" "09" and "1" "31."

Chinese characters matching the regular expression: [u4e00-u9fa5]
Matching double-byte characters (including Chinese characters included): [^ x00-xff]
Blank lines matching the regular expression: n [s |] * r
HTML tags matching the regular expression: / <(.*)>.*|< (.*) /> /
Both spaces matching the regular expression: (^ s *) | (s * $)
Email addresses match the regular expression: w +([-+.] w +) * @ w +([-.] w +) *. w +([-.] w +) *
Website URL matching the regular expression: http:// ([w-]+.)+[ w-]+(/[ w-./?%&=]*)?

(1) Applications: Calculation of the length of string (a double-byte character length of 2, ASCII character 1)
String.prototype.len = function () (return this.replace ([^ x00-xff] / g, "aa"). Length;)

(2) Application: javascript is not as trim as vbscript function, we can use this expression to achieve
String.prototype.trim = function ()
(
return this.replace (/ (^ s *) | (s * $) / g, "");
)
(3) Application: the use of regular expression IP addresses decomposition and conversion
function IP2V (ip) / / IP address into a corresponding numerical
(
re = / (d +). (d +). (d +). (d +) / g / / match the IP address regular expression
if (re.test (ip))
(
return RegExp. $ 1 * Math.pow (255,3)) + RegExp. $ 2 * Math.pow (255,2)) + RegExp. $ 3 * 255 + RegExp. $ 4 * 1
)
else
(
throw new Error ( "Not a valid IP address!")
)
)
(4) Applications: to extract from the URL address of the file name of the javascript program
s = "http://www.9499.net/page1.htm";
s = s.replace (/(.*/){ 0 ,}([^.]+).*/ ig, "$ 2"); / / Page1.htm
(5) Applications: restrictions on the use of regular expressions in the web form input text box
Use regular expressions to limit it only to input Chinese characters: onkeyup = "value =" / blog / value.replace (/["^ u4E00-u9FA5] / g, ")" onbeforepaste = "clipboardData.setData ( 'text', clipboardData . getData ( 'text'). replace (/ [^ u4E00-u9FA5] / g ,"))"
Restrictions on use of regular expressions can only enter the full-width characters are: onkeyup = "value =" / blog / value.replace (/["^ uFF00-uFFFF] / g, ")" onbeforepaste = "clipboardData.setData ( 'text', clipboardData.getData ( 'text'). replace (/ [^ uFF00-uFFFF] / g ,"))"
Restrictions on use of regular expressions can only enter a number: onkeyup = "value =" / blog / value.replace (/["^ d] / g, ")" onbeforepaste = "clipboardData.setData ( 'text', clipboardData.getData ( 'text'). replace (/ [^ d] / g ,"))"
Restrictions on use of regular expressions can only enter numbers and English: onkeyup = "value =" / blog / value.replace (/ [W] / g, "") "onbeforepaste =" clipboardData.setData ( 'text', clipboardData. getData ( 'text'). replace (/ [^ d] / g, "