function myFunction() {
var message, x;
message = document.getElementById("p01");
message.innerHTML = "";
x = document.getElementById("demo").value;
try {
if(x == "") throw "这里值是空的";
if(isNaN(x)) throw "这里的值不是一个数字";
x = Number(x);
if(x > 10) throw "太大了";
if(x < 5) throw "太小了";
}
catch(err) {
message.innerHTML = "错误信息: " + err + ".";
}
finally {
document.getElementById("demo").value = "";
}
}