<form action="b.php" method="get">

<input name="content" type="text" />

<label>

<input type="submit" name="Submit" value="提交">

</label>

</form>

<?

$str=$_GET[content];

echo $str."<br>";

$fp=fopen("kfz.txt","w");

fwrite($fp,$str);//写入

fclose($fp);

readfile("kfz.txt");//读取

?>