function CheckForBadChars(aFieldName, aText) {
	if (aText.indexOf('<') != -1) {
  	alert('Položka "' + aFieldName + '" obsahuje nepovolený znak "<".');
    return false;
  }
	if (aText.indexOf('>') != -1) {
  	alert('Položka "' + aFieldName + '" obsahuje nepovolený znak ">".');
    return false;
  }
	if (aText.indexOf('=') != -1) {
  	alert('Položka "' + aFieldName + '" obsahuje nepovolený znak "=".');
    return false;
  }
	if (aText.indexOf('"') != -1) {
  	alert('Položka \'' + aFieldName + '\' obsahuje nepovolený znak \'"\'.');
    return false;
  }
	return true; 
}

function ShowPreview(aID) {
    var lForm, re , t;
    
    if (navigator.appVersion.indexOf('MSIE') != -1)
      lForm = SendForm;
    else
      lForm = document.forms['SendForm'];

    document.cookie="preview(id)=" + aID + ";";
    document.cookie="preview(sender_name)=" + lForm.SENDER_NAME.value + ";";
    document.cookie="preview(sender_email)=" + lForm.SENDER_EMAIL.value + ";";
    document.cookie="preview(recipient_email)=" + lForm.RECIPIENT_EMAIL.value + ";";
    document.cookie="preview(send_date)=" + lForm.SEND_DATE.value + ";";
    document.cookie="preview(trace)=" + lForm.TRACE.value + ";";

		if (!CheckForBadChars("Jméno odesílatele",lForm.SENDER_NAME.value))
      return false;

    t = lForm.CARD_TEXT.value;
		if (!CheckForBadChars("Text přáníčka",lForm.CARD_TEXT.value))
      return false;
    re = / /gi;
    t = t.replace(re,"%20");
    re = /\r\n/gi;
    t = t.replace(re,"<br>");
    document.cookie="preview(card_text)=" + t + ";";
    
    if (parseInt(navigator.appVersion) >= 4)
      document.location = "show_card.asp?ID_PKJ=" + aID + "&TP=2";
    else
      parent.panel_mm.navigate("show_card.asp?ID_PKJ=" + aID + "&TP=2");
    return false;
  }