Regular expressions in JavaScript in several instances _ regular expressions

! Remove the processing of whitespace on both ends of a string

If you take the traditional approach, you might want to take the following approach.
Clear left Space
function Js_ltrim (DESTSTR)
{
if (deststr==null) return "";
var pos=0;
var retstr=new String (DESTSTR);
if (retstr.lenght==0) return retstr;
while (retstr.substring (pos,pos+1) = = "") pos++;
Retstr=retstr.substring (POS);
return (RETSTR);
}
Clear right space
function Js_rtrim (DESTSTR)
{
if (deststr==null) return "";
var retstr=new String (DESTSTR);
var pos=retstr.length;
if (pos==0) return retstr;
while (POS && retstr.substring (pos-1,pos) = "") pos--;
Retstr=retstr.substring (0,pos);
return (RETSTR);
}
Clear left and right spaces
function Js_trim (DESTSTR)
{
if (deststr==null) return "";
var retstr=new String (DESTSTR);
var pos=retstr.length;
if (pos==0) return retstr;
Retstr=js_ltrim (RETSTR);
Retstr=js_rtrim (RETSTR);
return retstr;
}

Using regular expressions, to remove the spaces on either side, just the following code
String.prototype.trim = function ()
{
Return This.replace (/(^\s*) | ( \s*$)/g, "");
}

One sentence is done,
The visible regular expression saves us a considerable amount of written code


! Check of mobile phone number

If you are using a traditional calibration method, you must complete the following three steps.
(1). Whether it is a number
(2). is 11-bit
(3). Whether the third digit is 5,6,7,8,9
If you use regular expression checksums, just the following code
function CheckMobile1 (form)
{
if (Form.mobile.value > "")
{
var reg=/13[5,6,7,8,9]\d{8}/;
if (Form.mobile.value.match (reg) = null)
{
Alert ("Please enter the correct mobile phone number!") ");
Form.mobile.focus (); return false;
}
}
return true;
}

From the above code can be seen verified mobile phone number only need to define a var reg=/13[5,6,7,8,9]\d{8}/, pattern matching string can complete the validity of the check

! The checksum of the URL,
Condition: Must begin with http://or https://, the port number must be between 1-65535, the following code completes the validation of the legality

OBJ: Data Objects
DISPSTR: Failure prompt Content Display string
function Checkurlvalid (obj, dispstr)
{
if (obj = null)
{
Alert ("Incoming object is null");
return false;
}
var str = obj.value;

var urlpatern0 =/^https?:\ /\/.+$/i;
if (!urlpatern0.test (str))
{
Alert (dispstr+ "illegal: Must start with ' http:\/\/' or ' https:\/\/')";
Obj.focus ();
return false;
}

var urlpatern2=/^https?:\ /\/([a-za-z0-9_-]) + (\.)?) * (: \d+)? +$/i;
if (!urlpatern2.test (str))
{
Alert (dispstr+ "port number must be a number and should be between 1-65535!");
Obj.focus ();
return false;
}


var urlpatern1 =/^https?:\ /\/([a-za-z0-9_-]) + (\.)?) * (: \d+)? (\/((\.)? (\?)? =?&? [a-za-z0-9_-] (\?)?) *) *$/i;

if (!urlpatern1.test (str))
{
Alert (dispstr+ "illegal, please check!");
Obj.focus ();
return false;
}

var s = "0";
var t = 0;
var re = new RegExp (": \\d+", "IG");
while ((arr = re.exec (str))!=null)
{
s = str.substring (Regexp.index+1,regexp.lastindex);

if (s.substring (0,1) = = "0")
{
Alert (dispstr+ "port number cannot begin with 0!");
Obj.focus ();
return false;
}

T = parseint (s);
if (t<1 | | t >65535)
{
Alert (dispstr+ "port number must be a number and should be between 1-65535!");
Obj.focus ();
return false;
}
}
return true;
}

To the URL of the checksum, it appears that there are a lot of code, this is because to give error prompts, otherwise just var urlpatern1 =/^https?:\ /\/([a-za-z0-9_-]) + (\.)?) * (: \d+)? (\/((\.)? (\?)? =?&? [a-za-z0-9_-] (\?)?) *) *$/i; You can verify that the URL is valid.


JavaScript Regular expression Test
/*********************************************************************************
* Eo_jslib.js
* JavaScript Regular expression test
**********************************************************************************/

The checksum is all made up of numbers
function IsDigit (s)
{
var patrn=/^[0-9]{1,20}$/;
if (!patrn.exec (s)) return false
return True
}

Verify Login Name: Can only enter 5-20 letters beginning with a letter, can be with numbers, "_", "." The string
function Isregisterusername (s)
{
var patrn=/^[a-za-z]{1} ([a-za-z0-9]|[. _]) {4,19}$/;
if (!patrn.exec (s)) return false
return True
}

Verify user name: You can enter only 1-30 strings that start with a letter
function Istruename (s)
{
var patrn=/^[a-za-z]{1,30}$/;
if (!patrn.exec (s)) return false
return True
}

Verify password: Can only enter 6-20 letters, numbers, underscores
function ispasswd (s)
{
var patrn=/^ (\w) {6,20}$/;
if (!patrn.exec (s)) return false
return True
}

Check ordinary telephone, fax number: You can "+" start, in addition to numbers, can contain "-"
function Istel (s)
{
var patrn=/^[+]{0,1} (\d) {1,3}[]? ([-]? (\d) {1,12}) +$/;
var patrn=/^[+]{0,1} (\d) {1,3}[]? ([-]? ((\d) | []) {1,12}) +$/;
if (!patrn.exec (s)) return false
return True
}

Check mobile phone Number: Must start with a number, in addition to the number, can contain "-"
function Ismobil (s)
{
var patrn=/^[+]{0,1} (\d) {1,3}[]? ([-]? ((\d) | []) {1,12}) +$/;
if (!patrn.exec (s)) return false
return True
}

Check ZIP code
function Ispostalcode (s)
{
var patrn=/^[a-za-z0-9]{3,12}$/;
var patrn=/^[a-za-z0-9]{3,12}$/;
if (!patrn.exec (s)) return false
return True
}

Verify Search Keywords
function Issearch (s)
{
var patrn=/^[^ ' ~!@#$%^&* () +=|\\\][\]\{\}:; ' \,.<>/?] {1} [^ ' ~!@$%^& () +=|\\\] [\]\{\}:;' \,.<>?] {0,19}$/;
if (!patrn.exec (s)) return false
return True
}

function IsIP (s)//by zergling
{
var patrn=/^[0-9.] {1,20}$/;
if (!patrn.exec (s)) return false
return True
}