function showhide(id) { // montre/cache en alternance une partie d'un texte
  if (document.getElementById) {
    //el = document.getElementById(id);
    var el = new getObj(id);
    if (el){
	    if (el.style.display == 'none') {
	      el.style.display = '';
	    } else {
	      el.style.display = 'none';
	    }
    }
  }
}


function permute(id,t1,t2) { // montre/cache en alternance une partie d'un texte
  if (document.getElementById) {
    if (document.getElementById(id).innerHTML == t1) {
      document.getElementById(id).innerHTML = t2;
    } else {
      document.getElementById(id).innerHTML = t1;
     }
  }
}


function show(id) { // montre l'élément id
  if (document.getElementById) {
    var el = new getObj(id);
    if (el.style){
	    if (el.style.display == 'none') {
	      el.style.display = '';
	    } 
    }
  }
}


function hide(id) { // cache l'élément id
  if (document.getElementById) {
    var el = new getObj(id);
    if (el.style){
	    if (el.style.display != 'none') {
	      el.style.display = 'none';
	    }
    }
  }
}

function cochedecoche(id,p) { 
    el = document.getElementById(id);
    if (el.style){
	    if (el.style.display == 'none') {
	      el.style.display = '';
	      el.value=p;
	      boite.checked=true;
	    } else {
	      el.style.display = 'none';
	      el.value='';
	      boite.checked=false;
	    }
    }
  }

function getObj(name){
  if (document.getElementById){
		this.obj = document.getElementById(name);
		if(this.obj) {
			this.style = document.getElementById(name).style;
			this.innerHTML=document.getElementById(name).innerHTML;
		}
	}
	else if (document.all){
		this.obj = document.all[name];
		if(this.obj) {
			this.style = document.all[name].style;
			this.innerHTML=document.all[name].innerHTML;
		}
	}
	else if (document.layers){
		this.obj = document.layers[name];
		if(this.obj) {
			this.style = document.layers[name];
			this.innerHTML=document.layers[name].innerHTML;
		}
	}
}

function bascule(id,t1,t2){
    el = document.getElementById(id);
		if (el.innerHTML==t1) {el.innerHTML=t2;}
		else {el.innerHTML=t1;}
	}

function valider_couverture(id,val) {
    el = document.getElementById(id);
    el.value=val;
  }