// JavaScript Document

//browser detection
			var strUserAgent = navigator.userAgent.toLowerCase(); 
			var isIE = strUserAgent.indexOf("msie") > -1; 
			var isNS6 = strUserAgent.indexOf("netscape6") > -1; 
			var isNS4 = !isIE && !isNS6  && parseFloat(navigator.appVersion) < 5; 
			
			//regular expressions
			//var reValidChars = /\d/;
			//var reValidString = /^\d*$/;
			var reValidChars = /\w/;			
			var reValidString = /^\w*$/;			
			//var reKeyboardChars = /[\x00\x03\x08\x0D\x16\x18\x1A]/;
			var reKeyboardChars = /[a-zA-Z0-9_ \x00\x03\x08\x0D\x16\x18\x1A]/;
			var reClipboardChars = /[cvxz]/i;
			
			//mask functions
			function maskKeyPress(objEvent,idioma) {
				var iKeyCode, strKey, objInput;  
				
				if (isIE) {
				    iKeyCode = objEvent.keyCode;
					objInput = objEvent.srcElement;
				} else {
				    iKeyCode = objEvent.which;
					objInput = objEvent.target;
				}
				
				strKey = String.fromCharCode(iKeyCode);
				
				if (isValid(objInput.value)) {
					objInput.validValue = objInput.value;
					//if (!reValidChars.test(strKey) && !reKeyboardChars.test(strKey) && !checkClipboardCode(objEvent, strKey)) {
					if (!reValidChars.test(strKey) && !reKeyboardChars.test(strKey) && !checkClipboardCode(objEvent, strKey)) {
						//alert("Invalid Character Detected!\nKeyCode = " + iKeyCode + "\nCharacter =" + strKey);
						alert(idioma);
						return false;
					} 
				} else {
					alert(idioma);
					objInput.value = objInput.validValue;
					return false;
				}
			}
			
			function checkClipboardCode(objEvent, strKey) {
			  	if (isNS6)
			    	return objEvent.ctrlKey && reClipboardChars.test(strKey);
			  	else
			    	return false;
			}
			
			function isValid(strValue) {
				return reValidString.test(strValue) || strValue.length == 0;			
			}
			
			function maskChange(objEvent) {
			  	var objInput;
			
			  	if (isIE) {
			    	objInput = objEvent.srcElement; 
			  	} else {
			    	objInput = objEvent.target;
			  	}
			 
			  	if (!isValid(objInput.value)) {
			    	alert("Datos incorrectos");
					objInput.value = objInput.validValue || "";
					objInput.focus();
			    	objInput.select(); 
			  	} else {
					objInput.validValue = objInput.value;
				}
			}
			
			function maskPaste(objEvent) {
				var strPasteData = window.clipboardData.getData("Text");
				var objInput = objEvent.srcElement;
				
		  		if (!isValid(strPasteData)) {
		    		alert("Datos incorrectos");
		    		objInput.focus();
					return false;
		  		}
			}