PHP文件上传功能 -- 多文件上传

这一节内容主要介绍PHP上传文件的多文件上传功能。

只要以数组形式来命名表单中的文件上传标记，即可实现多个文件同时上传。

下面我们来看一个例子：
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<form enctype="multipart/form-data" action="<?=$_SERVER[‘PHP_SELF‘]?>" method="post">
    <input type="hidden" name="MAX_FILE_SIZE" value="104857600" />
    <table>
        <tr>
            <td>上传文件：<input name="upload_file[]" type="file" size="50" /></td>
        </tr>
        <tr>
            <td>上传文件：<input name="upload_file[]" type="file" size="50" /></td>
        </tr>
        <tr>
            <td>上传文件：<input name="upload_file[]" type="file" size="50" /></td>
        </tr>
        <tr>
            <td>上传文件：<input name="upload_file[]" type="file" size="50" /></td>
        </tr>
        <tr>
            <td><input type="submit" name="submit" value="上传"/></td>
        </tr>
    </table>
</form>

<?php
    function upload($file_error, $file_tmp_name, $file_name){
        $info = "";

        if($file_name == "")
            return $info;

        switch($file_error){
            case UPLOAD_ERR_INI_SIZE:
                $info = $file_name. ": 文件大小超过了服务器的限制";
                break;
            case UPLOAD_ERR_FORM_SIZE:
                $info = $file_name. ": 文件大小超过了浏览器的限制";
                break;
            case UPLOAD_ERR_PARTIAL:
                $info = $file_name. ": 只上传了部分文件";
                break;
            case UPLOAD_ERR_NO_FILE:
                $info = $file_name. ": 没有文件被上传";
                break;
            case UPLOAD_ERR_NO_TMP_DIR:
                $info = $file_name. ": 找不到临时文件夹";
                break;
            case UPLOAD_ERR_CANT_WRITE:
                $info = $file_name. ": 文件写入失败";
                break;
            case UPLOAD_ERR_OK:
                $upload_dir = ‘./‘.iconv("UTF-8","gb2312",$file_name);
                if(file_exists($upload_dir)){
                    $info = $file_name.": 同名文件已经存在";
                }else{
                    if(move_uploaded_file($file_tmp_name,$upload_dir)){
                        $info = $file_name.": 文件上传成功";
                    }else{
                        $info = $file_name.": 文件上传失败";
                    }
                }
                break;
        }
        return $info;
    }

    if(isset($_POST[‘submit‘])){
        $info = ‘‘;
        $count = count($_FILES[‘upload_file‘][‘name‘]);
        for($i=0; $i<$count; ++$i){
            if($_FILES[‘upload_file‘][‘name‘][$i] == "")
                continue;
            $info = upload(
                $_FILES[‘upload_file‘][‘error‘][$i],
                $_FILES[‘upload_file‘][‘tmp_name‘][$i],
                $_FILES[‘upload_file‘][‘name‘][$i]
            );
        }
        echo $info;
    }

?>
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代码执行结果如下：


注意：

1、<input name="upload_file[]" type="file" size="50" />中， name="upload_file[]"一定要以数组形式命名，不然就会出现错误：    “Uninitialized string offset: 0”，这句话的意思是你的数组key值越界了

2、$_FILES[‘upload_file‘][‘name‘][$i]中， upload_file是表单中上传文件标记符的名称，多文件上传时，数组$_FILES的第三维下标会自动从0开始依次编号。