function validateForm(theForm)
{
       if (theForm.name.value == ""){alert("No first name specified. Please enter your first name."); return false;}
	   else
	   if (theForm.family.value == ""){alert("No family name specified. Please enter your family name."); return false;}
	   else
	   
	   if (checkInternationalPhone(theForm.phone.value)==false){
		alert("Please Enter a Valid Phone Number"); return false;}
	   else
	   if (echeck(theForm.email.value)==false){
		 return false;}
		else 
		if (theForm.referrer.value == ""){alert("No referrer specified. Please tell us how you heard about London Translations."); return false;}
	   else
		if (theForm.languages.value == ""){alert("No language(s) specified. Please enter the language(s) which you would like your interpreters to interpret between"); return false;}
	   else
	   if (theForm.city.value == ""){alert("No city specified. Please enter the city in which your event will be held"); return false;}
	   else
	   if (theForm.country.value == ""){alert("No country specified. Please enter the country in which your event will be held"); return false;}
	   else
		if (!checkDate(theForm)){alert("Date invalid. Please enter the date which you would like your interpreting assignment to start in dd/mm/yyyy format");	   return false;}
 	   else
	   if (theForm.duration.value == ""){alert("No duration specified. Please enter how long you need your interpreters for."); return false;}
	   else
		
		return true;
}

// ------------------------------------------

function checkInternationalPhone(strPhone)

{

// Declaring required variables
	var digits = "0123456789";
// non-digit characters which are allowed in phone numbers
	var phoneNumberDelimiters = "()- ";
// characters which are allowed in international phone numbers
// (a leading + is OK)
	var validWorldPhoneChars = phoneNumberDelimiters + "+";
// Minimum no of digits in an international phone no.
	var minDigitsInIPhoneNumber = 10;

function isInteger(s)
{   
   var i;
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) return false;
    }
    // All characters are numbers.
    return true;
}

function stripCharsInBag(s, bag)
{   var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

s=stripCharsInBag(strPhone,validWorldPhoneChars);
return (isInteger(s) && s.length >= minDigitsInIPhoneNumber);
}

// ------------------------------------------


function echeck(str) {

		var at="@"
		var dot="."
		var lat=str.indexOf(at)
		var lstr=str.length
		var ldot=str.indexOf(dot)
		if (str.indexOf(at)==-1){
		   alert("Invalid E-mail ID")
		   return false
		}

		if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
		   alert("Invalid E-mail ID")
		   return false
		}

		if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
		    alert("Invalid E-mail ID")
		    return false
		}

		 if (str.indexOf(at,(lat+1))!=-1){
		    alert("Invalid E-mail ID")
		    return false
		 }

		 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
		    alert("Invalid E-mail ID")
		    return false
		 }

		 if (str.indexOf(dot,(lat+2))==-1){
		    alert("Invalid E-mail ID")
		    return false
		 }
		
		 if (str.indexOf(" ")!=-1){
		    alert("Invalid E-mail ID")
		    return false
		 }

 		 return true					
	}








/**********************************************************************/ 
/*Function name :isDigit(theDigit) */ 
/*Usage of this function :test for an digit */ 
/*Input parameter required:thedata=string for test whether is digit */ 
/*Return value :if is digit,return true */ 
/* else return false */ 
/**********************************************************************/ 
function isDigit(theDigit) 
{ 
var digitArray = new Array('0','1','2','3','4','5','6','7','8','9'),j; 

for (j = 0; j < digitArray.length; j++) 
{if (theDigit == digitArray[j]) 
return true 
} 
return false 

} 
/*************************************************************************/ 
/*Function name :isPositiveInteger(theString) */ 
/*Usage of this function :test for an +ve integer */ 
/*Input parameter required:thedata=string for test whether is +ve integer*/ 
/*Return value :if is +ve integer,return true */ 
/* else return false */ 
/*function require :isDigit */ 
/*************************************************************************/ 
function isPositiveInteger(theString) 
{ 
var theData = new String(theString) 

if (!isDigit(theData.charAt(0))) 
if (!(theData.charAt(0)== '+')) 
return false 

for (var i = 1; i < theData.length; i++) 
if (!isDigit(theData.charAt(i))) 
return false 
return true 
} 
/**********************************************************************/ 
/*Function name :isDate(s,f) */ 
/*Usage of this function :To check s is a valid format */ 
/*Input parameter required:s=input string */ 
/* f=input string format */ 
/* =1,in mm/dd/yyyy format */ 
/* else in dd/mm/yyyy */ 
/*Return value :if is a valid date return 1 */ 
/* else return 0 */ 
/*Function required :isPositiveInteger() */ 
/**********************************************************************/ 
function isDate(s,f) 
{var a1=s.split("/"); 
var a2=s.split("-"); 
var e=true; 
if ((a1.length!=3) && (a2.length!=3)) 
{ 
e=false; 
} 
else 
{if (a1.length==3) 
var na=a1; 
if (a2.length==3) 
var na=a2; 
if (isPositiveInteger(na[0]) && isPositiveInteger(na[1]) && isPositiveInteger(na[2])) 
{ if (f==1) 
{var d=na[1],m=na[0]; 
} 
else 
{var d=na[0],m=na[1]; 
} 
var y=na[2]; 
if (((e) && (y<1000)||y.length>4)) 
e=false 
if (e) 
{ 
v=new Date(m+"/"+d+"/"+y); 
if (v.getMonth()!=m-1) 
e=false; 
} 
} 
else 
{ 
e=false; 
} 
} 
return e 
} 
function checkDate(theForm) 
{ 

if (isDate(theForm.date.value,0))//dd/mm/yyyy format 
return true; 
else 
return false; 
}