throw 声明

  1. <html>
  2. <body>
  3. <script type="text/javascript">
  4. var x=prompt("请输入 0 至 10 之间的数：","")
  5. try
  6. { 
  7. if(x>10) 
  8.   throw "Err1" 
  9. else if(x<0)
  10.   throw "Err2"
  11. else if(isNaN(x))
  12.   throw "Err3"
  13. } 
  14. catch(er)
  15. {
  16. if(er=="Err1") 
  17.   alert("错误！该值太大！")
  18. if(er == "Err2") 
  19.   alert("错误！该值太小！") 
  20. if(er == "Err3") 
  21.   alert("错误！该值不是数字！") 
  22. }
  23. </script>
  24. </body>
  25. </html>