​x
 
<!DOCTYPE html>
<html>
<body>
​
<p>请输入 5 到 10 之间的数字：</p>
​
<input id="demo" type="text">
<button type="button" onclick="myFunction()">检测输入</button>
<p id="p01"></p>
​
<script>
function myFunction() {
  var message, x;
  message = document.getElementById("p01");
  message.innerHTML = "";
  x = document.getElementById("demo").value;
  try { 
    if(x == "")  throw "是空的";
    if(isNaN(x)) throw "不是数字";
    x = Number(x);
    if(x < 5)  throw "太小";
    if(x > 10)   throw "太大";
  }
  catch(err) {
    message.innerHTML = "输入：" + err;
  }
}
</script>
​
</body>
</html>
​