JavaScript中字符串处理的一些函数

<script type="text/javascript">
(function(){

var methods = {

camelize: function() {

/**
* Returns string with all instances of
* "-word" replaced with "Word", E.g.
* "background-color" -> "backgroundColor"
**/

return this.replace(/\-(\w)/g, function( $0, $1 ) {
return $1.toUpperCase();
});

},

contains: function( what ) {

/**
* Returns boolean indicating whether
* or not a substring exists within the string
**/

what = typeof what === 'string' ? what : what.toString();

return this.indexOf( what ) > -1;

},

count: function( what ) {

/**
* Returns a number indicating how many times
* a substring or regex is matched within the string
**/

if ( Object.prototype.toString.call(what) !== '[object RegExp]' ) {
what = what.toString().replace(/\$\^\[\]\{\}\(\)\?\:\.\+\*/g, '\\$1');
}

what = RegExp( what ? what.source : '.', 'g' );

return (this.match( what ) || []).length;

},

enclose: function( a, b ) {

/**
* Returns string with all instances
* of -w replaced with W, e.g.
* "background-color" -> "backgroundColor"
**/

return (a = a || '') + this + (b ? b : a);

},

extract: function( regex, n ) {

/**
* Matches the string against the passed regex
* and the returns the group specified by _n_
*
* E.g.
*     ('hi @boo and @adam').extract(/@(\w+)/g, 1);
*       => ['boo', 'adam']
*
* If the regex is global then an array is returned
* otherwise just the matched group is returned.
**/

n = n === undefined ? 0 : n;

if ( !regex.global ) {
return this.match(regex)
|| '';
}

var match,
extracted = [];

while ( (match = regex.exec(this)) ) {
extracted[extracted.length] = match
|| '';
}

return extracted;

},

forEach: function( fn ) {

/**
* Runs the passed function on every character,
* similar to Array.prototype.forEach
**/

var c, i = -1;

while ( (c = this[++i]) ) {
fn.call( this, c, i );
}

return true;

},

forEachWord: function( fn ) {

/**
* Runs the passed function on every word,
* similar to Array.prototype.forEach
**/

var string = this,
i = -1;

string.replace(/\b([\w\-]+)\b/g, function( match, word ){
fn.call( string, word, ++i );
return match;
});

return true;

},

linkify: function( replacement ) {

/**
* Returns a string with all URLs replaced
* with HTML anchor tags.
**/

return this.replace(/(^|\s)((?:f|ht)tps?:\/\/[^\s]+)/g, replacement || '$1<a href="$2">$2</a>');

},

many: function( n ) {

/**
* Returns a string which is made up of
* _n_ instances of the original string.
* E.g. "a".many(3) => "aaa"
**/

return Array(n ? n + 1 : 2).join(this);

},

randomize: function() {

/**
* Randomizes a string; messes up all the characters.
* E.g. "abcdef".randomize() => "bcfdea"
**/

return this.split('').sort(function(){
return Math.random() > 0.5 ? -1 : 1;
}).join('');

},

remove: function( what ) {

/**
* Returns a string with all matches of
* what (regex) removed.
**/

return this.replace( what || /./g, '' );

},

removefromLength : function (A,B)
{
/**
*	Returns string
*	How long is where to begin a string is removed
**/
var s='';
if(A>0)s=this.substring(0,A);
if(A+B<this.length)s+=this.substring(A+B,this.length);
return s;
},

reverse: function() {

/**
* Returns the string, reversed.
**/

return this.split('').reverse().join('');

},

shorten: function( length, token ) {

/**
* Shortens the string by the specified amount
* and appends the token.
* E.g.
* "this is a long sentance".shorten(10, '...');
*  => "this is a ..."
**/

var substrd = this.substring( 0, length || this.length );

return substrd + ( substrd === this ? '' : (token || '') );

},

sort: function() {

/**
* Runs the Array.sort() method on every
* character of the string.
**/

return Array.prototype.sort.apply( this.split(''), arguments ).join('');

},

toDOM: function() {

/**
* Returns the DOM representation of the string,
* in the form of an array of DOM nodes.
**/

var temp = document.createElement('div');
temp.innerHTML = this;

return Array.prototype.slice.call( div.childNodes );

},

trim: function() {

/**
* Returns the string with leading and
* trailing spaces removed.
**/

return this.replace(/^\s\s*/, '').replace(/\s\s*$/, '');

},

wrap: function( width, brk, cut ) {

/**
* Wraps the string.
* E.g.
* "the dog realllly wet".wrap(4, '<br/>')
*  => "the <br/>dog <br/>realllly <br/>wet"
**/

brk = brk || '\n';
width = width || 75;
cut = cut || false;

if (!this) { return this; }

var regex = '.{1,' +width+ '}(\\s|$)' + (cut ? '|.{' +width+ '}|.+$' : '|\\S+?(\\s|$)');

return this.match( RegExp(regex, 'g') ).join( brk );

},

//
endsWith : function (A,B)
{

/**
*	To determine whether a string to specify the end of the string
**/

var C=this.length;
var D=A.length;
if(D>C)return false;
if(B) {
var E=new RegExp(A+'$','i');
return E.test(this);
}else return (D==0||this.substr(C-D,D)==A);
},

//
startsWith : function(str)
{

/**
*	To determine whether a string starts with the specified string
**/

return this.substr(0, str.length) == str;
},

replaceAll:function (a,b) {

/**
*	replaceAll
*	eg：str.ReplaceAll([/a/g,/b/g,/c/g],["aaa","bbb","ccc"])
**/

var c=this;
for(var i=0;i<a.length;i++) {
c=c.replace(a[i],b[i]);
};
return C;
},

isEmail : function()
{

/**
*	Returns boolean  and
*	Check whether the correct email
**/

return /^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/.test(this);
},

inTrim:function(s){

/**
*	Returns string
*	remove the Spaces in the string
**/

return s.replace( /\s/g,"");
},

checkPassWordLevelA:function()
{

/**
*	Returns number
*	Determine the password security level
**/

var n=0;
if (/\d/.test(this)) n ++;
if (/[a-z]/.test(this)) n ++;
if (/[A-Z]/.test(this)) n ++;
if (this.length == 6) n=1;
return n;
},

checkPassWordLevelB : function()
{

/**
*	Returns number
*	Determine the password security level
**/

var grade=0;
if (this.length >= 6 && this.length <= 9)
{
grade = 1;
}
if (this.length >= 10 && this.length <= 15)
{
grade = 2;
}
if (this.length >= 16 && this.length <= 20)
{
grade = 3;
}
return grade;
},

isIDCard : function()
{

/**
*	Returns boolean
*	Whether effective id card (China
**/

var iSum=0;
var info="";
var sId = this;

var aCity={11:"北京",12:"天津",13:"河北",14:"山西",15:"内蒙古",21:"辽宁",22:"吉林",23:"黑龙江",31:"上海",32:"江苏",33:"浙江",34:"安徽",35:"福建",36:"江西",37:"山东",41:"河南",42:"湖北",43:"湖南",44:"广东",45:"广西",46:"海南",50:"重庆",51:"四川",52:"贵州",53:"云南",54:"西藏",61:"陕西",62:"甘肃",63:"青海",64:"宁夏",65:"新疆",71:"台湾",81:"香港",82:"澳门",91:"国外"};

if(!/^\d{17}(\d|x)$/i.test(sId))
{
return false;
}
sId=sId.replace(/x$/i,"a");

if(aCity[parseInt(sId.substr(0,2))]==null)
{
return false;
}

var sBirthday=sId.substr(6,4)+"-"+Number(sId.substr(10,2))+"-"+Number(sId.substr(12,2));

var d=new Date(sBirthday.replace(/-/g,"/"))

if(sBirthday!=(d.getFullYear()+"-"+ (d.getMonth()+1) + "-" + d.getDate()))
{
return false;
}
for(var i = 17;i>=0;i--)
{
iSum += (Math.pow(2,i) % 11) * parseInt(sId.charAt(17 - i),11);
}

if(iSum%11!=1)
{
return false;
}
return true;

},

isNumeric : function(flag)
{

/**
*	Verify whether the Numbers
**/

if(isNaN(this))
{
return false;
}

switch(flag)
{

case null:
case "":
return true;
case "+":
return /(^\+?|^\d?)\d*\.?\d+$/.test(this);
case "-":
return /^-\d*\.?\d+$/.test(this);
case "i":
return /(^-?|^\+?|\d)\d+$/.test(this);
case "+i":
return /(^\d+$)|(^\+?\d+$)/.test(this);
case "-i":
return /^[-]\d+$/.test(this);
case "f":
return /(^-?|^\+?|^\d?)\d*\.\d+$/.test(this);
case "+f":
return /(^\+?|^\d?)\d*\.\d+$/.test(this);
case "-f":
return /^[-]\d*\.\d$/.test(this);
default:
return true;
}
},

checkChinese : function()
{

/**
*	Returns boolean
*	Check whether the Chinese characters
**/
var reg=/^[\u0391-\uFFE5]+$/ ;
//      [\u4E00-\u9FA5];
return reg.test(this);
},

isMobile : function()
{

/**
*	Returns string
*	Check whether a mobile phone number eg. 13723450922
**/

var reg = /^(13|14|15|17|18)[0-9]{9}$/;
return reg.test(this);
},

ChineseLength : function()
{
/**
*	Returns boolean
*	Returns the length of the character, a Chinese is 2
**/
return this.replace(/[^\x00-\xff]/g,"**").length;
},

format : function(){
var args = arguments;
return this.replace(/\{(\d+)\}/g,function(m,i,o,n){
return args[i];
});
}

};

/* This is where each method is added to String.prototype
( assuming it's not already there ) */
for (var method in methods) {
String.prototype[method] = String.prototype[method] || methods[method];
}

})();

var s = '中国人';

console.log(s.ChineseLength());