PHP文件上传操作和封装
PHP文件上传主要两个步骤:
1.首先前端html写好文件表单上传网页
2.在前端点提交时,web服务器php脚本通过超全局变量$_FILES和一个move_uploaded_file函数搞定
前端html如下:
<meta charset="utf-8"> <title>文件上传</title>注:表单上传文件时,method必须用post,且须声明是enctype="multipart/form-data"
2.服务器php脚本upload.php代码如下:
<?phpif (move_uploaded_file($_FILES['uploadpic']['tmp_name'], './fileupload/'.$_FILES['uploadpic']['name'])){ echo "ok"; }else { echo "fail";}注:可以用print_r($_FILES)打印查看超全局变量里面放的内容,可以看到文件的相关信息都放在这个变量里面;如
array ( 'uploadpic' => array ( 'name' => '1客栈首页.jpg', 'type' => 'image/jpeg', 'tmp_name' => 'C:\\Windows\\Temp\\php3F1C.tmp', 'error' => 0, 'size' => 1706919, ),)ok从变量的数组里面可以知道上传的文件名,文件类型、web服务器临时存放图片的位置(如果要更改临时存放路径,可以去php.ini里面更改),错误信息和文件大小(限制文件上传大小,也可以到php.ini里修改)。
error有如下几种:
其值为 0,没有错误发生,文件上传成功。
其值为 1,上传的文件超过了 php.ini 中 upload_max_filesize 选项限制的值。
其值为 2,上传文件的大小超过了 HTML 表单中 MAX_FILE_SIZE 选项指定的值。
其值为 3,文件只有部分被上传。
其值为 4,没有文件被上传。
其值为 6,找不到临时文件夹。PHP 4.3.10 和 PHP 5.0.3 引进。
其值为 7,文件写入失败。PHP 5.1.0 引进。
==========文件上传封装类============
<?phpclass UpFile{ public $maxsize=2; //1M public $errmsg=""; public $ext = "png,jpg,bmp,gif"; //上传大小是否符合 function isAllowSize($size) { if($size <= $this->maxsize*1024*1024) { return true; } else { return false; } } //判断后缀名是否符合 function isAllowExt($ext) { return in_array(strtolower($ext), explode(',', $this->ext)); } //获取文件后缀名 function getFileExt($file) { $arr = explode('.', $file); return end($arr); } //图片上传,$pickey为input的name值,$save_path保存路径 function upload($pickey,$save_path) { if(!isset($_FILES[$pickey])) { return false; } if($_FILES[$pickey]['error'] !=0) { $this->errmsg = $this->getErrorType($_FILES[$pickey]['error']); return false; } $file_ext = $this->getFileExt($_FILES[$pickey]['name']); echo $file_ext; if(!$this->isAllowExt($file_ext)) { $this->errmsg = "文件后缀名不符合"; return false; } echo $_FILES[$pickey]['size']; if(!$this->isAllowSize($_FILES[$pickey]['size'])) { $this->errmsg = "大小超过限制"; return false; } $str = "abcdefjhijkmnpqrst23456789"; $filename = date("YmdHis",time()).substr(str_shuffle($str), 0,6); $dir = $this->makeDir($save_path); if(move_uploaded_file($_FILES[$pickey]['tmp_name'], $dir.'/'.$filename.'.'.$file_ext)) { return true; } else { $this->errmsg = "上传失败"; return false; } } //创建目录 function makeDir($save_path) { $path = $save_path.'/'.date("Ymd",time()); if(is_dir($path) || mkdir($path,0777,true)) //不存在该目录文件,创建 { echo $path; return $path; } else { return false; } } //错误类型分析 function getErrorType($error) { $errmsg = ""; switch ($error) { case 0: $errmsg = "文件上传成功"; break; case 1: $errmsg = "上传的文件超过了 php.ini 中 upload_max_filesize 选项限制的值"; break; case 2: $errmsg = "上传文件的大小超过了 HTML 表单中 MAX_FILE_SIZE 选项指定的值"; break; case 3: $errmsg = "文件只有部分被上传"; break; case 4: $errmsg = "没有文件被上传"; break; case 6: $errmsg = "找不到临时文件夹"; break; case 7: $errmsg = "文件写入失败"; break; } return $errmsg; }}
使用如下:
<?phpinclude 'upfile.class.php';$upfile = new UpFile();if($upfile->upload('uploadpic', "./fileupload")){ echo "ok";}else{ echo $upfile->errmsg;}

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