复制代码代码如下：
<html>
<head>
<Title>新しいドキュメント</title>
<Meta name = "generator" content = "editplus">
<Meta name = "Author" content = "">
<Meta name = "keywords" content = "">
<メタ名= "説明" content = "">
</head>
<スクリプト言語= "javascript">
関数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 = "">
<入力型= "text" id = "username" name = "username">
<入力型= "ボタン" name = "只读" value = "read" onclick = "isreadonly（）;">
<入力型= "ボタン" name = "可写" value = "write" onclick = "readwrite（）;">
</form>
</body>
</html>
<！ -
「「読む」按钮、入力框不能书写、且变灰；点击「書き込み」、入力框恢复。
- >