写了一个简单的html/php上传的网页，在安卓和电脑上都正常，但ipad上都有问题，即图片上传名称都自动变成image.jpg

ipad的safari或chrome都是这样的问题。

<!--表单-->
<div id="upload">
<form action="upload_file.php" method="post"
    enctype="multipart/form-data">
    <label for="file">Filename:</label>
    <input type="file" name="file" id="file" />
    <br />
    <input type="submit" name="submit" value="Submit" />
</form>
</div>

// upload_file.php
<?php
error_reporting(E_ERROR| E_PARSE);
session_start();
$name=$_SESSION["free_print_name"];
$phone=$_SESSION["free_print_phone"];
if (!file_exists("/var/www/upload_files/".$phone)) {
    mkdir("/var/www/upload_files/".$phone);
}
$DIR="/var/www/upload_files/".$phone."/";
$temp_array=explode('.', $_FILES["file"]["name"]);
$postfix=$temp_array[count($temp_array)-1];
if (
    ($postfix=="pdf"
        || $postfix == "doc"
        || $postfix == "docx"
        || $postfix == "rtf"
        || $postfix == "ppt"
        || $postfix == "jpg"
        || $postfix == "jpeg"
        || $postfix == "png"
        || $postfix == "psd")
    && ($_FILES["file"]["size"] < 20000000)) {
    if ($_FILES["file"]["error"] > 0) {
        // echo "Return Code: " . $_FILES["file"]["error"] . "<br />";
    } else {
        echo "Upload: " . $_FILES["file"]["name"] . "<br />";
        echo "Type: " . $_FILES["file"]["type"] . "<br />";
        echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />";
        echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br />";
        if (file_exists($DIR . $_FILES["file"]["name"])) {
            echo $_FILES["file"]["name"] . " already exists. ";
            header('Location: http://59.78.7.9/index.html');
        } else {
            move_uploaded_file($_FILES["file"]["tmp_name"], $DIR. $_FILES["file"]["name"]);
            echo "Stored in: " . $DIR . $_FILES["file"]["name"];
            header('Location: http://59.78.7.9/index.html');
        }
    }
} else {
    echo "Invalid file, you can't upload files of ".$postfix;
}
?>