function checka(obj)
{
  if (document.getElementById('anlass').value == 'Bitte auswählen...') 
  {
  document.getElementById('channel').style.display = 'none';
  document.getElementById('allgemein').style.display = 'none';
  document.getElementById('themac').style.display = 'none';   
  document.getElementById('absender').style.display = 'none';
  document.getElementById('message').style.display = 'none';
  document.getElementById('thema_c').value = 'Bitte das Thema auswählen!';
  document.getElementById('thema_allg').value = 'Bitte das Thema auswählen!';
  document.getElementById('cliste').value = 'Bitte einen Channel auswählen!'
  }
  if (document.getElementById('anlass').value == 'Allgemeine Frage')
  {
  document.getElementById('channel').style.display = 'none';
  document.getElementById('allgemein').style.display = 'block';
  document.getElementById('themac').style.display = 'none';   
  document.getElementById('absender').style.display = 'none';
  document.getElementById('message').style.display = 'none';
  document.getElementById('thema_c').value = 'Bitte das Thema auswählen!';
  document.getElementById('thema_allg').value = 'Bitte das Thema auswählen!';
  document.getElementById('cliste').value = 'Bitte einen Channel auswählen!'  
  }
  
  if (document.getElementById('anlass').value == 'Frage zu einem Channel?')
  {
  document.getElementById('channel').style.display = 'block';
  document.getElementById('allgemein').style.display = 'none';
  document.getElementById('themac').style.display = 'none';   
  document.getElementById('absender').style.display = 'none';
  document.getElementById('message').style.display = 'none';
  document.getElementById('thema_c').value = 'Bitte das Thema auswählen!';
  document.getElementById('thema_allg').value = 'Bitte das Thema auswählen!';
  document.getElementById('cliste').value = 'Bitte einen Channel auswählen!'  
  }  
}
  
function checkb(obj)
{
  if (document.getElementById('cliste').value != 'Bitte einen Channel auswählen!') 
  {
  document.getElementById('channel').style.display = 'block';
  document.getElementById('allgemein').style.display = 'none';
  document.getElementById('themac').style.display = 'block';  
  document.getElementById('absender').style.display = 'none';
  document.getElementById('message').style.display = 'none';
  } 
  else 
  {
  document.getElementById('channel').style.display = 'block';
  document.getElementById('allgemein').style.display = 'none';
  document.getElementById('themac').style.display = 'none';  
  document.getElementById('themac').style.display = 'none';  
  document.getElementById('absender').style.display = 'none';
  document.getElementById('message').style.display = 'none';
  }
}

function checkc(obj) 
{ 
  if (document.getElementById('thema_allg').value != 'Bitte das Thema auswählen!' )
  {
  document.getElementById('channel').style.display = 'none';
  document.getElementById('allgemein').style.display = 'block';
  document.getElementById('themac').style.display = 'none';  
  document.getElementById('absender').style.display = 'block';
  document.getElementById('message').style.display = 'block';
  } 
  else 
  {
  document.getElementById('channel').style.display = 'none';
  document.getElementById('allgemein').style.display = 'block';
  document.getElementById('themac').style.display = 'none';  
  document.getElementById('absender').style.display = 'none';
  document.getElementById('message').style.display = 'none';
  }
}

function checkd(obj) 
{ 
  if (document.getElementById('thema_c').value != 'Bitte das Thema auswählen!' )
  {
  document.getElementById('channel').style.display = 'block';
  document.getElementById('allgemein').style.display = 'none';
  document.getElementById('themac').style.display = 'block';  
  document.getElementById('absender').style.display = 'block';
  document.getElementById('message').style.display = 'block';
  } 
  else 
  {
  document.getElementById('channel').style.display = 'block';
  document.getElementById('allgemein').style.display = 'none';
  document.getElementById('themac').style.display = 'block';  
  document.getElementById('absender').style.display = 'none';
  document.getElementById('message').style.display = 'none';
  }
}