(function($){
	$.fn.alphanumeric = function(p) { 
		p = $.extend({
			ichars: "!@#$%^&*()+=[]\\\';,/{}|\":<>?~`.- ",
			nchars: "",
			allow: "",
			contextmenu: false
		}, p);
		return this.each(function() {
			if(p.nocaps) p.nchars += "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
			if(p.allcaps) p.nchars += "abcdefghijklmnopqrstuvwxyz";
			
			s = p.allow.split('');
			for( i = 0; i < s.length; i++ ) if( p.ichars.indexOf(s[i]) != -1 ) s[i] = "\\" + s[i];
			p.allow = s.join('|');
			
			var reg = new RegExp(p.allow,'gi');
			var ch = p.ichars + p.nchars;
			ch = ch.replace(reg,'');
			$(this).keypress(function(e) {
				if(!e.charCode) {
					k = String.fromCharCode(e.which);
				} else {
					k = String.fromCharCode(e.charCode);
				}
				if(ch.indexOf(k) != -1) e.preventDefault();
				if(e.ctrlKey&&k=='v') e.preventDefault();
			});
			
			$(this).bind('contextmenu', function() { if( !p.contextmenu ) return false; });
		});
	};
	$.fn.numeric = function(p) {
		var az = "abcdefghijklmnopqrstuvwxyz";
		az += az.toUpperCase();
		p = $.extend({ nchars: az }, p);
		
		return this.each (function() { $(this).alphanumeric(p); });
	};
	$.fn.alpha = function(p) {
		var nm = "1234567890";
		p = $.extend({ nchars: nm }, p);
		return this.each(function() { $(this).alphanumeric(p); });
	};
})(jQuery);