51help TIY
码：
<!DOCTYPE html> <html> <body> <script> function myFunction() { try { var x=document.getElementById("demo").value; if(x=="") throw "值为空"; if(isNaN(x)) throw "不是数字"; if(x>10) throw "太大"; if(x<5) throw "太小"; } catch(err) { var y=document.getElementById("mess"); y.innerHTML="错误：" + err + "。"; } } </script> <h1> JavaScript 程序</h1> <p>请输入 5 到 10 ：</p> <input id="demo" type="text"> <button type="button" onclick="myFunction()"></button> <p id="mess"></p> </body> </html>
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