function trimAllSpace(str)
{ 
		var str1 = ''; 
		var i = 0; 
		
		while(i != str.length) 
		{ 
		
			if(str.charAt(i) != ' ') str1 = str1 + str.charAt(i); 
			i ++; 
		} 
		return str1;
 }

 function trimString(str) 
 { 
	var str1 = ''; 
	var i = 0; 
	while ( i != str.length) 
	{ 
		if(str.charAt(i) != ' ') str1 = str1 + str.charAt(i); 
		i++; 
	} 
	return str1; 
 }
 
  function isValidEmail(strEmail){
		  validRegExp = /^[^@]+@[^@]+\.[a-z]{2,}$/i;
		 
			if ((strEmail==null) || (strEmail.length == 0))  return false;
			strEmail = trimAllSpace(strEmail);
		
		   // search email text for regular exp matches
		    if (strEmail.search(validRegExp) == -1) 
		   {
		      alert('Indirizzo email non valido.');
		      return false;
		    } 
		    return true; 
}