function checkInquiry(){
		if (document.inquiry.name.value == ""){
			alert("Your name is required");
			return false;
	}
	if (document.inquiry.Clientname.value == ""){
			alert("Your name is required");
			return false;
	}	
		if (document.inquiry.Clientcompany.value == ""){
			alert("Your company is required");
			return false;
	}
		if (document.inquiry.Clientphone_number.value == "" ) { 
			alert("Please enter your phone number.");
			return false;
	}
		if (document.inquiry.ClientEmail.value == "" || (document.inquiry.ClientEmail.value.indexOf("@",0) == -1||document.inquiry.ClientEmail.value.indexOf(".",0) == -1)) { 
			alert("Please enter a valid E-mail address");
			return false;
	}
		//if (document.inquiry.phone_number.value == "" ) { 
			//alert("Please enter your phone number.");
			//return false;
	//}
		//if (document.inquiry.prefer.value == ""){
			//alert("Please choose a preferred time of contact.");
			//return false;
	//}
		//if (document.inquiry.Email.value == "" || (document.inquiry.Email.value.indexOf("@",0) == -1||document.inquiry.Email.value.indexOf(".",0) == -1)) { 
			//alert("Please enter a valid E-mail address");
			//return false;
	//}
	 
		//if (document.inquiry.type_of_service.value == ""){
			//alert("Please specify what type of service you require.");
			//return false;
	//}	
}

function checkInquiry2(){
		if (document.inquiry2.name.value == ""){
			alert("Your name is required");
			return false;
	}	
		if (document.inquiry2.company.value == ""){
			alert("Your company is required");
			return false;
	}
		if (document.inquiry2.phone_number.value == "" ) { 
			alert("Please enter your phone number.");
			return false;
	}
		if (document.inquiry2.Email.value == "" || (document.inquiry2.Email.value.indexOf("@",0) == -1||document.inquiry2.Email.value.indexOf(".",0) == -1)) { 
			alert("Please enter a valid E-mail address");
			return false;
	}

}

function handlerNum() {
	e = window.event;
	// number 0~9 : 48~57  ,  keypad 0~9: 96~105  ,  8: backspace ,  46: delete
	if(e.keyCode >= 48 && e.keyCode <= 57 || e.keyCode >= 96 && e.keyCode <=105 || e.keyCode == 8 || e.keyCode == 46)
	{
		if(e.keyCode == 48 || e.keyCode ==96) // press 0
		{
			if(document.contactus.Number_of_books.value == "") // press 0 first in empty inputbox
			{
				e.returnValue = false; // nothing
				alert("0 is not available to insert first.");
			}
			else // press 0 after insert other numbers in inputbox
			{
				return; // insert
			}
		}
		else // if it is not 0
		{
			return; // insert
		}
	}
	else // if it is not number
	{
		e.returnValue = false; // nothing
		alert("please insert number.");
	}
}