控制input框只讀可以防止用戶對數據的更改，在某些情況下還是比較實用的，下面使用js來完成這個只讀實現
代碼如下: <html> <head> <title> New Document </title> <meta name="Generator" content="EditPlus"> <meta name="Author" content=""> <meta name="Keywords" content=""> <meta name="Description" content=""> </head> <script language="JavaScript"> function isreadonly(){ var obj = document.getElementById("username"); obj.setAttribute("readOnly",true); obj.style.backgroundColor="#d2d2d2"; } function readwrite(){ var obj = document.getElementById("username"); obj.setAttribute("readOnly",false); obj.style.backgroundColor="#ffffff"; } </script> <body> <form name="addform" id="addform" method="post" action="" > <input type="text" id="username" name="username"> <input type="button" name="只讀" value="read" onclick="isreadonly();"> <input type="button" name="可寫" value="write" onclick="readwrite();"> </form> </body> </html> <!-- 點擊“read”按鈕，input框不能書寫，且變灰；點擊“write”按鈕，input框恢復。 -->