提示：您可以先修改部分代碼再運行
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>判斷數字是否為兩位元</title><style>body{font:12px/1.5 arial;text-align:center;}.f-text{width:50px;border:1px solid #ccc;background:#f0f0f0;font-family:inherit;padding:3px;margin-right:10px;}</style><script type="text/javascript">window.onload = function (){var aInput = document.getElementsByTagName("input");var aSpan = document.getElementsByTagName("span")[0];var i = 0;aInput[0].onkeyup = function (){this.value = this.value.replace(/[^d]/,"")}aInput[1].onclick = function (){(aInput[0].value == "") ?alert("請輸入數字！") :alert(/^d{2}$/.test(parseInt(aInput[0].value)) ? "√ 是兩位元" : "這是" + aInput[0].value.length + "位元");}};</script></head><body><input type="text" class="f-text" /><input type="button" value="是否為兩位元" /></body></html></td> </tr></table>
提示：您可以先修改部分代碼再運行
