function handleListChangetbt(theList) {
  var numSelected = theList.selectedIndex;
  if (numSelected != 0) {
    textValue = document.getElementById('text').value;
    textValue = textValue + theList.options[numSelected].value;
    document.getElementById('text').value = textValue;
    theList.selectedIndex = 0;
  }
}
var clear = 0;
function checkClear(theEle) {
  if (clear == 0) {
    clear = 1;
    theEle.value = "";
  }
}
function showhidetbt(id){ 
  if (document.getElementById) { 
    obj = document.getElementById(id); 
    if (obj.style.display == "none") { 
      obj.style.display = ""; 
    } else { 
      obj.style.display = "none"; 
    } 
  } 
} 
function validate(form) {
  selIndex1 = form["wl_srclang"].selectedIndex;
  selIndex2 = form["wl_trglang"].selectedIndex;
  if (form["wl_srclang"].options[selIndex1].value == form["wl_trglang"].options[selIndex2].value) {
    alert("请选择两种不同的语言。\
    form["wl_trglang"].focus();
    return false;
  }
  return true;
}