Match double-byte characters (including kanji): [^\x00-\xff]
Application: Calculates the length of a string (a double-byte character length meter 2,ascii character 1)
String.prototype.len=function () {return This.replace ([^\x00-\xff]/g, "AA"). Length;
Regular expression that matches a blank line: \n[\s|] *\r
Regular expression matching HTML tags:/< (. *) >.*<\/>|< (. *) \/>/
Regular expression matching the leading and trailing spaces: (^\s*) | (\s*$)
Application: There is no trim function like VBScript in JavaScript, and we can use this expression to do the following:
String.prototype.trim = function () {
Return This.replace (/(^\s*) | ( \s*$)/g, "");
}
Use regular expressions to decompose and convert IP addresses:
The following is a JavaScript program that matches an IP address with a regular expression and translates an IP address into a corresponding value:
function IP2V (IP) {
re=/(\d+) \. (\d+) \. (\d+) \. (\d+)/g//matching regular expressions for IP addresses
if (Re.test (IP)) {
Return Regexp.*math.pow (255,3)) +regexp.*math.pow (255,2)) +regexp.*255+regexp.*1
}
else {
throw new Error ("not a valid IP address!")
}
}
However, the above program without regular expression, and directly with the split function decomposition may be more simple, the program is as follows:
var ip= "10.100.20.168"
Ip=ip.split (".")
Alert ("IP value is:" + (IP[0]*255*255*255+IP[1]*255*255+IP[2]*255+IP[3]*1))
Regular expression matching email address: \w+ ([-+.] \w+) *@\w+ ([-.] \w+) *\.\w+ ([-.] \w+) *
Regular expression matching URL URL:/http ([\w-]+\.) +[\w-]+ (/[\w-./?%&=]*)?
An algorithmic program that uses regular expressions to remove repeated characters from a string:
var s= "Abacabefgeeii"
var s1=s.replace (/(.). */g, "")
var re=new RegExp ("[" +s1+ "]", "G")
var s2=s.replace (Re, "")
Alert (S1+S2)//Result: ABCEFGI
A JavaScript program that extracts file names from URL addresses with regular expressions, with the following result as Page1
S= "Http://www.9499.net/page1.htm"
S=s.replace (/(. *\/) ([^\.] +). */ig, "")
Alert (s)
Use regular expressions to restrict the entry of text boxes in Web Forms:
Use regular expression restrictions to enter only Chinese:
/[^\u4e00-\u9fa5]/g, ') '/[^\u4e00-\u9fa5]/g, ') '
You can only enter full-width characters with regular expression restrictions:
/[^\uff00-\uffff]/g, ') '/[^\uff00-\uffff]/g, ') '
You can only enter numbers with regular expression restrictions:
/[^\d]/g, ') '/[^\d]/g, ') '
Use regular expression restrictions to enter only numbers and English:
/[\w]/g, ') '/[^\d]/g, ')
The above describes some of the regular expression Java PHP some commonly used regular expression character conversion, including the regular expression Java aspects of the content, I hope the PHP tutorial interested in a friend helpful.
