php----图片上传封装类：单张，多张图片上传，生成缩略图

<?php
/**
* 功能： 单张，多张图片上传，生成缩略图
* Class ImgUpload
*/
class ImgUpload
{
private $file;                  //文件信息
private $fileList;            //文件列表
private $inputName;     //标签名称
private $uploadPath;    //上传路径
private $fileMaxSize;    //最大尺寸
private $uploadFiles;   //上传文件

//允许上传的文件类型
private $allowExt = array('bmp', 'jpg', 'jpeg', 'png', 'gif');

/**
* @param $inputName input标签的name属性
* @param $uploadPath 文件上传路径
*/
public function __construct($inputName, $uploadPath)
{
$this->inputName = $inputName;
$this->uploadPath = $uploadPath;
$this->fileList = array();
$this->file = $file = array(
'name' => null,
'type' => null,
'tmp_name' => null,
'size' => null,
'errno' => null,
'error' => null
);
}

/**
* 设置允许上传的图片后缀格式
* @param $allowExt 文件后缀数组
*/
public function setAllowExt($allowExt)
{
if (is_array($allowExt)) {
$this->allowExt = $allowExt;
} else {
$this->allowExt = array($allowExt);
}
}

/**
* 设置允许上传的图片规格
* @param $fileMaxSize 最大文件尺寸
*/
public function setMaxSize($fileMaxSize)
{
$this->fileMaxSize = $fileMaxSize;
}

/**
* 获取上传成功的文件数组
* @return mixed
*/
public function getUploadFiles()
{
return $this->uploadFiles;
}

/**
* 得到文件上传的错误信息
* @return array|mixed
*/
public function getErrorMsg()
{
if (count($this->fileList) == 0) {
return $this->file['error'];
} else {
$errArr = array();
foreach ($this->fileList as $item) {
array_push($errArr, $item['error']);
}
return $errArr;
}
}

/**
* 初始化文件参数
* @param $isList
*/
private function initFile($isList)
{
if ($isList) {
foreach ($_FILES[$this->inputName] as $key => $item) {
for ($i = 0; $i
< count($item); $i++) {
if ($key == 'error') {
$this->
fileList[$i]['error'] = null;
$this->fileList[$i]['errno'] = $item[$i];
} else {
$this->fileList[$i][$key] = $item[$i];
}
}
}
} else {
$this->file['name'] = $_FILES[$this->inputName]['name'];
$this->file['type'] = $_FILES[$this->inputName]['type'];
$this->file['tmp_name'] = $_FILES[$this->inputName]['tmp_name'];
$this->file['size'] = $_FILES[$this->inputName]['size'];
$this->file['errno'] = $_FILES[$this->inputName]['error'];
}
}

/**
* 上传错误检查
* @param $errno
* @return null|string
*/
private function errorCheck($errno)
{
switch ($errno) {
case UPLOAD_ERR_OK:
return null;
case UPLOAD_ERR_INI_SIZE:
return '文件尺寸超过服务器限制';
case UPLOAD_ERR_FORM_SIZE:
return '文件尺寸超过表单限制';
case UPLOAD_ERR_PARTIAL:
return '只有部分文件被上传';
case UPLOAD_ERR_NO_FILE:
return '没有文件被上传';
case UPLOAD_ERR_NO_TMP_DIR:
return '找不到临时文件夹';
case UPLOAD_ERR_CANT_WRITE:
return '文件写入失败';
case UPLOAD_ERR_EXTENSION:
return '上传被扩展程序中断';
}
}

/**
* 上传文件校验
* @param $file
* @throws Exception
*/
private function fileCheck($file)
{
//图片上传过程是否顺利
if ($file['errno'] != 0) {
$error = $this->errorCheck($file['errno']);
throw new Exception($error);
}
//图片尺寸是否符合要求
if (!empty($this->fileMaxSize) && $file['size'] > $this->fileMaxSize) {
throw new Exception('文件尺寸超过' . ($this->fileMaxSize / 1024) . 'KB');
}
//图片类型是否符合要求
$ext = pathinfo($file['name'], PATHINFO_EXTENSION);
if (!in_array($ext, $this->allowExt)) {
throw new Exception('不符合要求的文件类型');
}
//图片上传方式是否为HTTP
if (!is_uploaded_file($file['tmp_name'])) {
throw new Exception('文件不是通过HTTP方式上传的');
}
//图片是否可以读取
if (!getimagesize($file['tmp_name'])) {
throw new Exception('图片文件损坏');
}
//检查上传路径是否存在
if (!file_exists($this->uploadPath)) {
mkdir($this->uploadPath, null, true);
}
}

/**
* 单文件上传，成功返回true
* @return bool
*/
public function acceptSingleFile()
{
$this->initFile(false);
try {
$this->fileCheck($this->file);
// $md_name = md5(uniqid(microtime(true), true)) . '.' . pathinfo($this->file['name'], PATHINFO_EXTENSION);

// 简单设置图片名
$md_name = uniqid() . '.' . pathinfo($this->file['name'], PATHINFO_EXTENSION);

if (move_uploaded_file($this->file['tmp_name'], $this->uploadPath . $md_name)) {
$this->uploadFiles = array($this->uploadPath . $md_name);
} else {
throw new Exception('文件上传失败');
}
} catch (Exception $e) {
$this->file['error'] = $e->getMessage();
} finally {
if (file_exists($this->file['tmp_name'])) {
unlink($this->file['tmp_name']);
}
}
return empty($this->file['error']) ? true : false;
}

/**
* 多文件上传，全部成功返回true
* @return bool
*/
public function acceptMultiFile()
{
$this->initFile(true);
$this->uploadFiles = array();
for ($i = 0; $i
< count($this->
fileList); $i++) {
try {
$this->fileCheck($this->fileList[$i]);
$ext = pathinfo($this->fileList[$i]['name'], PATHINFO_EXTENSION);
// $md_name = md5(uniqid(microtime(true), true)) . '.' . $ext;

// 简单设置图片名
$md_name = uniqid() . '.' . $ext;

if (move_uploaded_file($this->fileList[$i]['tmp_name'], $this->uploadPath . $md_name)) {
array_push($this->uploadFiles, $this->uploadPath . $md_name);
} else {
throw new Exception('文件上传失败');
}
} catch (Exception $e) {
$this->fileList[$i]['error'] = $e->getMessage();
} finally {
if (file_exists($this->fileList[$i]['tmp_name'])) {
unlink($this->fileList[$i]['tmp_name']);
}
}
}
foreach ($this->fileList as $item) {
if (!empty($item['error'])) {
return false;
}
}
return true;
}

/**
* 生成缩略图：
* @param $picName 图片名. 为上传后图片的完整路径. 获取： $imgUpload->getUploadFiles()[0]
* @param $max_w 缩略图宽度
* @param $max_h 缩略图高度
* @param $pre   缩缩略图前缀
* @return bool
*/
public function imgUpdateSize($picName, $max_w=100, $max_h=100, $pre='_s'){
#1 获取图片的基本信息
$info = getimagesize($picName);
$w = $info[0];
$h = $info[1];

#2 获取图片的类型
switch ($info[2]){
case 1:         #gif
$im = imagecreatefromgif($picName);
break;
case 2:         #jpeg
$im = imagecreatefromjpeg($picName);
break;
case 3:         #png
$im = imagecreatefrompng($picName);
break;
default :
die('image style error!');
}

#3 计算缩放比例
if(($max_w/$w) > ($max_h/$h)){
$b = $max_h/$h;
}else{
$b = $max_w/$w;
}

#4 计算缩放后的尺寸
$nw = floor($w*$b);
$nh = floor($h*$b);

#5 创建一个新的图像源 -目标画布
$nim = imagecreatetruecolor($nw, $nh);

# 等比例缩放
imagecopyresampled($nim, $im, 0, 0, 0, 0, $nw, $nh, $w, $h);

#6 输出图片 -按源图像的类型输出
$picInfo = pathinfo($picName);        #解析源图像的名子与路径信息

$new_picName = $picInfo['dirname'].'/'.$picInfo['filename'] .$pre.'.'.$picInfo['extension'];    #拼装新图像名

switch ($info[2]){
case 1:         #gif
imagejpeg($nim, $new_picName);
break;
case 2:         #jpeg
imagejpeg($nim, $new_picName);
break;
case 3:         #png
imagepng($nim, $new_picName);
break;
default :
die('image style error!');
}

#7 释放图片资源
imagedestroy($im);
imagedestroy($nim);

return $new_picName;
}
}