在php中，处理上传文件信息也是很方便的，以下是一个简单的示例，有助于大家理解php是如何接收与处理上传文件信息的。
代码：
<?php
/**
* php 处理上传文件
* by www.jb200.com
*/
$maxsize=28480;
if (!$HTTP_POST_VARS['submit']) {
$error=" ";
}
if (!is_uploaded_file($HTTP_POST_FILES['upload_file']['tmp_name']) AND !isset($error)) {
$error = "<b>上传文件不能为空!</b><br /><br />";
unlink($HTTP_POST_FILES['upload_file']['tmp_name']);
}
if ($HTTP_POST_FILES['upload_file']['size'] > $maxsize AND !isset($error)) {
$error = "<b>错误：上传文件大小必须小于 $maxsize 字节.</b><br /><br />";
unlink($HTTP_POST_FILES['upload_file']['tmp_name']);
}
if (!isset($error)) {
move_uploaded_file($HTTP_POST_FILES['upload_file']['tmp_name'],
"uploads/".$HTTP_POST_FILES['upload_file']['name']);
print "上传成功。";
exit;
}
else
{
echo ("$error");
}
?>
<html>
<head>
</head>
<body>
<form action="<?php echo(htmlspecialchars($_SERVER['PHP_SELF']))?>"
method="post" enctype="multipart/form-data">
选择上传文件:<br />
<input type="file" name="upload_file" size="80">
<br />
<input type="submit" name="submit" value="开始上传">
</form>
</body>
</html>