JavaScript中字符串处理的一些函数

废话，不多说，直接上代码

<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)[n] || '';
            }

            var match,
                extracted = [];

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

            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());