输出计算结果：output
<!DOCTYPE>
<html>
<head>
<meta charset="utf-8">
</head>
<body>
<form oninput="x.value=parseInt(a.value)+parseInt(b.value)" method="post">
<input type="range" id="a" value="50" min="0" max="100">100 +
<input type="number" id="b" value="50"> =
<output name="x" for="a b"> 100</output>
</from>
</body>
</html>
接收多行文本输入：textarea
<!DOCTYPE>
<html>
<head>
<meta charset="utf-8">
</head>
<body>
<form method="post">
<textarea>I am the bone of my sword.
Steel is my body,and fire is my blood.
I have created over thousand blades.
Unknown to death,
Nor known to life.
Have with stood pain to create many weapons.
Yet,those hands will never hold anything.
So as I pray,unlimited blade works.</textarea>
</from>
</body>
</html>
- rows和cols属性来调整框的大小，单位是字符
<!DOCTYPE>
<html>
<head>
<meta charset="utf-8">
</head>
<body>
<form method="post">
<textarea rows="10" cols="45">I am the bone of my sword.
Steel is my body,and fire is my blood.
I have created over thousand blades.
Unknown to death,
Nor known to life.
Have with stood pain to create many weapons.
Yet,those hands will never hold anything.
So as I pray,unlimited blade works.
</textarea>
</from>
</body>
</html>
-
wrap,有3个值：soft，hard，off
- soft：会自动换行，但不提交换行符
- hard：会自动换行，但提交换行符,如何设置了hard，则必须同时指定cols属性
- off：不会自动换行