19. 检查一段字符串是否全由数字组成 <script language="javascript"><!-- function checkNum(str){return str.match(//D/)==null} alert(checkNum("1232142141")) alert(checkNum("123214214a1")) // --></script> 20. 获得一个窗口的大小 document.body.clientWidth,document.body.clientHeight 21. 怎么判断是否是字符 if (/[^/x00-/xff]/g.test(s)) alert("含有汉字"); else alert("全是字符"); 22.TEXTAREA自适应文字行数的多少 <textarea rows=1 name=s1 cols=27 onpropertychange="this.style.posHeight=this.scrollHeight"> </textarea> 23. 日期减去天数等于第二个日期 <script language=javascript> function cc(dd,dadd) { //可以加上错误处理 var a = new Date(dd) a = a.valueOf() a = a - dadd * 24 * 60 * 60 * 1000 a = new Date(a) alert(a.getFullYear() + "年" + (a.getMonth() + 1) + "月" + a.getDate() + "日") } cc("12/23/2002",2) </script> 24. 选择了哪一个Radio <HTML><script language="vbscript"> function checkme() for each ob in radio1 if ob.checked then window.alert ob.value next end function </script><BODY> <INPUT name="radio1" type="radio" value="style" checked>Style <INPUT name="radio1" type="radio" value="barcode">Barcode <INPUT type="button" value="check" onclick="checkme()"> </BODY></HTML> 25.获得本页url的request.servervariables("")集合 Response.Write "<TABLE border=1><!-- Table Header --><TR><TD><B>Variables</B></TD><TD><B>value</B></TD></TR>" for each ob in Request.ServerVariables Response.Write "<TR><TD>"&ob&"</TD><TD>"&Request.ServerVariables(ob)&"</TD></TR>" next Response.Write "</TABLE>"