function ShowOrderBlock(id,size)
{
ClearSelection();
document.getElementById("bsize"+size).className="onesizeselected";
$("#orderform").load(encodeURI("/shop/showorderblock.php?id="+id+"&size="+size+"&r="+Math.random())); 
}

function ClearSelection() { 
 //Populate the array with all the page tags 
 var allPageTags=document.getElementsByTagName("*"); 
 //Cycle through the tags using a for loop 
 for (i=0; i<allPageTags.length; i++) { 
 //Pick out the tags with our class name 
 if (allPageTags[i].className=="onesizeselected") { 
 //Manipulate this in whatever way you want 
 allPageTags[i].className="onesize";
 } 
 } 
}