function validate_required(field,alerttxt)
{
with (field)
{
if (value==null||value==""||value=='empty')
  {alert(alerttxt);return false;}
else {return true}
}
}

function validate_form(thisform)
{
with (thisform)
{
if (validate_required(year,"Year must be filled out!")==false)
  {year.focus();return false;}
if(isNaN(price.value))
  {price.focus();alert("Price must contain only numeric characters!");return false}
if(isNaN(mileage.value))
  {price.focus();alert("Mileage must contain only numeric characters!");return false}
if (validate_required(make,"Make must be filled out!")==false)
  {make.focus();return false;}
if (validate_required(model,"Model must be filled out!")==false)
  {model.focus();return false;}
if (validate_required(address,"Address must be filled out!")==false)
  {address.focus();return false;}  
if (validate_required(body,"Body style must be filled out!")==false)
  {body.focus();return false;}
  
if (validate_required(price,"Price must be filled out!")==false)
  {price.focus();return false;}
if (validate_required(mileage,"Mileage must be filled out!")==false)
  {mileage.focus();return false;}
if (validate_required(exteriorcolor,"Exterior color must be filled out!")==false)
  {exteriorcolor.focus();return false;}
if (validate_required(interiorcolor,"Interior color must be filled out!")==false)
  {interiorcolor.focus();return false;}
if (validate_required(transmission,"Transmission must be filled out!")==false)
  {transmission.focus();return false;}
if (validate_required(doors,"Doors number must be filled out!")==false)
  {doors.focus();return false;}
if (validate_required(vin,"VIN must be filled out!")==false)
  {vin.focus();return false;}
if (validate_required(fueltype,"Fuel type must be filled out!")==false)
  {fueltype.focus();return false;}
if (validate_required(cylinders,"Cylinders must be filled out!")==false)
  {cylinders.focus();return false;}
if (validate_required(drivetrain,"Drive train must be filled out!")==false)
  {drivetrain.focus();return false;}
if (validate_required(city,"City must be filled out!")==false)
  {city.focus();return false;}
if (validate_required(state,"State must be filled out!")==false)
  {state.focus();return false;}
if (validate_required(contactname,"Contact name must be filled out!")==false)
  {contactname.focus();return false;}
if (validate_required(emailaddress,"Email must be filled out!")==false)
  {emailaddress.focus();return false;}
if (validate_required(sellertype,"Seller type must be filled out!")==false)
  {sellertype.focus();return false;}
if (validate_required(pnonenumber1,"Phone number must be filled out!")==false)
  {phonenumber1.focus();return false;}
if (validate_required(pnonenumber2,"Phone number must be filled out!")==false)
  {phonenumber2.focus();return false;}
if (validate_required(pnonenumber3,"Phone number must be filled out!")==false)
  {phonenumber3.focus();return false;}
}
}

var downStrokeField;
function autojump(fieldName,nextFieldName,fakeMaxLength)
{
var myForm=document.forms[document.forms.length - 1];
var myField=myForm.elements[fieldName];
myField.nextField=myForm.elements[nextFieldName];

if (myField.maxLength == null)
   myField.maxLength=fakeMaxLength;

myField.onkeydown=autojump_keyDown;
myField.onkeyup=autojump_keyUp;
}

function autojump_keyDown()
{
this.beforeLength=this.value.length;
downStrokeField=this;
}

function autojump_keyUp()
{
if (
   (this == downStrokeField) && 
   (this.value.length > this.beforeLength) && 
   (this.value.length >= this.maxLength)
   )
   this.nextField.focus();
downStrokeField=null;
}

function numbersonly(myfield, e, dec)
{
var key;
var keychar;

if (window.event)
   key = window.event.keyCode;
else if (e)
   key = e.which;
else
   return true;
keychar = String.fromCharCode(key);

// control keys
if ((key==null) || (key==0) || (key==8) || 
    (key==9) || (key==13) || (key==27) )
   return true;

// numbers
else if ((("0123456789").indexOf(keychar) > -1))
   return true;

// decimal point jump
else if (dec && (keychar == "."))
   {
   myfield.form.elements[dec].focus();
   return false;
   }
else
   return false;
}

function letternumber(e)
{
var key;
var keychar;

if (window.event)
   key = window.event.keyCode;
else if (e)
   key = e.which;
else
   return true;
keychar = String.fromCharCode(key);
keychar = keychar.toLowerCase();

// control keys
if ((key==null) || (key==0) || (key==8) || 
    (key==9) || (key==13) || (key==27) )
   return true;

// alphas and numbers
else if ((("abcdefghijklmnopqrstuvwxyz0123456789").indexOf(keychar) > -1))
   return true;
else
   return false;
}


function contact(e)
{
var key;
var keychar;

if (window.event)
   key = window.event.keyCode;
else if (e)
   key = e.which;
else
   return true;
keychar = String.fromCharCode(key);
keychar = keychar.toLowerCase();

// control keys
if ((key==null) || (key==0) || (key==8) || 
    (key==9) || (key==13) || (key==27) )
   return true;

// alphas and numbers
else if (((" -'abcdefghijklmnopqrstuvwxyz").indexOf(keychar) > -1))
   return true;
else
   return false;
}