<html> <head> <title>计算是否是闰年</title> <script language="javascript"> function leap() ...{ var year = document.year.input.value if(year == "") ...{ alert("请不要提交空数据,重新输入请点击《否》,退出请点击是"); window.close(); } if(year % 4 == 0) ...{ if(year % 100 == 0) ...{ if(year % 400 == 0) document.year.result.value = 1 else document.year.result.value = 0 } else document.year.result.value = 1 } else document.year.result.value = 0 } </script> </head><body> <form name="year"> <font color="red" face="宋体" size="7px">1代表是闰年 0代表不是闰年</font><p> <input type="text" name="input" value="" size="5"> <input type="text" name="result" value="" size="5"> <input type="button" name="select" value="计算" onClick="leap()"> <input type="reset" value="清除"> </form></body></html>