文件的常用操作-2018年8月28日

今天学习了文件，目录以及文件上传的知识：

代码：

实例

<form action="<?php echo htmlspecialchars($_SERVER['PHP_SELF']);?>"method="post" enctype="multipart/form-data">
    <input type="hidden" name="MAX_FILE_SIZE" value="542488">
    <fieldset>
            <legend align="center">文件上传</legend>
            <p><strong>选择文件</strong><input type="file" name="upload"></p>
    </fieldset>
            <p align="center"><button type="submit" name="submit">上传</button></p>

</form>
<?php
    if($_SERVER['REQUEST_METHOD']='POST') {
        if (isset($_FILES['upload'])) {
            $allow = ['image/jpg', 'image/jpeg', 'image/png'];
            if (in_array($_FILES['upload']['type'], $allow)) {
                if (move_uploaded_file($_FILES['upload']['tmp_name'], "./upload/{$_FILES['upload']['name']}")) {
                    echo "<script>alert('文件上传成功')</script>";
                }
            } else {
                echo '<script>alert(\'仅允许上传jpg和png格式的图片\')</script>';
            }
        }
        if ($_FILES['upload']['error'] > 0) {
            echo '<p>错误原因是:<strong>';
            switch ($_FILES['upload']['error']) {
                case 1:
                    echo '文件超过了php.ini配置中设置的大小';
                    break;
                case 2:
                    echo '文件超过了表单中常量设置的大小';
                    break;
                case 3:
                    echo '仅有部分文件被上传';
                    break;
                case 4:
                    echo '没有文件被上传';
                    break;
                case 6:
                    echo '没有可用的临时文件夹';
                    break;
                case 7:
                    echo '磁盘已满,写入失败';
                    break;
                case 8:
                    echo '上传意外中止';
                    break;

                default:
                    echo '系统未知错误';
                    break;
            }
            echo '</strong></p>';
            if (file_exists($_FILES['upload']['tmp_name']) && is_file($_FILES['upload']['tmp_name'])) {
                unlink($_FILES['upload']['tmp_name']);
            }
        }
    }else{
        echo '1';
    }
?>

实例

<?php
$dir=opendir('../6')or die('打开失败');
while(false!=($file=readdir($dir))){
    //print $file.'<br>';
   // print  nl2br($file);
    if ($file != "." && $file != "..") {
        print $file."<br>";
    }
}
closedir($dir);

echo '<hr>';