function check(fieldname,size,type,message)
{
if(typeof fieldname=='undefined')
{
alert('The field name is not in the specified form'+fieldname);
return false;
}
var a,b,c;

if(type=='PASSWORD')
{
var x=arguments[4].value;
a=fieldname.value;
if(a!=x)
{
alert(message);
  fieldname.focus();
  return(false);
}
}

if(type=='TEXT')
{
a=fieldname.value;
if(a.length<size)
  {
  alert(message);
  fieldname.focus();
  return(false);
  }
}

if(type=='EMAIL')
{
a=fieldname.value;
if(a.length<size || a.indexOf('@')<0 || a.indexOf('.')<0)
  {
  alert(message);
  fieldname.focus();
  return(false);
  }
}

if(type=='NUMBER')
{
a=fieldname.value;
if(a.length<size )
  {
  alert(message);
  fieldname.focus();
  return(false);
  }
 for(i=0;i<(a.length-1);i++)
  if(a.charAt(i)<'0' || a.charAt(i)>'9')
  {
  alert(message);
  fieldname.focus();
  return(false);
  }
}

if(type=='SELECT')
{
a=fieldname.value;
if(a=='Choose')
  {
  alert(message);
  fieldname.focus();
  return(false);
  }
}

if(type=='RADIO')
{
a=fieldname;
txtGenderLength = a.length;
		 var i=0;
		if(txtGenderLength > 1){
			for(GenIndex = 0; GenIndex < txtGenderLength; GenIndex++ ){
				if(a[GenIndex].checked == false){
					i=i+1;
				}
			}
		}
		if(i==txtGenderLength)
		{
			alert(message);
			return false;
		}	
}

if(type=='IMAGE')
{
a=fieldname.value;
if(a.length<size)
  {
 alert(message);
  fieldname.focus();
  return(false);
  }

b=a.lastIndexOf('.')+1;

c=a.substring(b);

if(c=='jpg'||c=='jpeg'||c=='png'||c=='gif')
return true;
else
{
alert(message+'<br>It should be a valid file of jpg,gif,png');
return false;
}

}

if(type=='SQL')
{
a=fieldname.value;
if(a.length<size)
  {
  alert(message);
  fieldname.focus();
  return(false);
  }

b=a.lastIndexOf('.')+1;

c=a.substring(b);

if(c=='sql')

return true;

else
{
alert('Selected file is not an valid SQL file');
return false;
}
}
}