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<!DOCTYPE html><html lang="en"><?php//! $_FILES: PHP超全局变量数量, 保存着上传文件的全部信息printf('<pre>%s</pre>', print_r($_FILES,true));//!isset: 检测变量是否已声明并且其值不为 nullif(isset($_FILES['my_pic'])){$name = $_FILES['my_pic']['name'];$tmpName = $_FILES['my_pic']['tmp_name'];$error = $_FILES['my_pic']['error'];if($error>0){$tips = '<span style="color:lightgreen">上传失败:</span>';switch($error){case 1 :$tips .='上传的文件超过了php.ini 中upload_max_filesize 选项限制的值';break;case 2 :$tips .='文件大小超过了上传表单中MAX_FILE_SIZE最大值';break;case 3 :$tips .='文件只有部分被上传';break;case 4 :$tips .='没有文件被上传';break;case 6 :$tips .='找不到临时目录';break;case 7 :$tips .='文件写入失败，请检查目录权限';break;}echo "<p>$tips</p>";}else{//! is_uploaded_file:判断文件是否是通过 HTTP POST 上传的if(is_uploaded_file($tmpName)){$allow = ['jpg','jpeg','png','gif'];//! pathinfo:返回文件路径的信息,//!如果没有传入 options ，将会返回包括以下单元的数组 array：dirname，basename 和 extension$ext = pathinfo($name)['extension'];// print_r($ext);//! in_array:检查数组中是否存在某个值if(in_array($ext,$allow)){// $path = 'C:\Users\Administrator\Desktop\后端学习质料\0427-1\up/';$path = 'C:/Users/Administrator/Desktop/后端学习质料/0427/up/';//!将目标文件名md5加密$dest =$path . md5($name) . '.' . $ext;//预览文件存放的地方$show = 'up/'.md5($name). '.' . $ext;// print_r($dest);//!move_uploaded_file: 将上传的文件移动到新位置if(move_uploaded_file($tmpName, $dest)){// move_uploaded_file($tmpName, $path);echo '<p style="color:red">上传成功</p>';echo "<img src='$show' width='200'>";}else{echo '<p style="color:lightblue">移动失败</p>';}}else{echo '<p style="color:lightblue">文件类型错误</p>';}}else{echo '<p style="color:lightblue">非法方式上传</p>';}}}?><head><meta charset="UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>单文件上传</title></head><body><!-- enctype:规定了form表单在发送到服务器时候，数据的编码方式 --><!-- multipart/form-data: 指定传输数据为二进制类型，比如图片、mp3、文件。 --><form action="" method="POST" enctype="multipart/form-data"><fieldset><legend>单文件上传</legend><!-- type="hidden"：隐藏域 --><!-- MAX_FILE_SIZE，意思是接收文件的最大尺寸，与后面的value的值对应 --><input type="hidden" name="MAX_FILE_SIZE" value="300000"><input type="file" name="my_pic"><button>上传</button></fieldset></form></body></html>
<!DOCTYPE html><html lang="en"><?phpprintf('<pre>%s</pre>',print_r($_FILES,true));foreach($_FILES as $file){if($file['error']>0){$tips = '<span style="color:lightgreen">上传失败:</span>';switch($file['error']){case 1 :$tips .='上传的文件超过了php.ini 中upload_max_filesize 选项限制的值';break;case 2 :$tips .='文件大小超过了上传表单中MAX_FILE_SIZE最大值';break;case 3 :$tips .='文件只有部分被上传';break;case 4 :$tips .='没有文件被上传';break;case 6 :$tips .='找不到临时目录';break;case 7 :$tips .='文件写入失败，请检查目录权限';break;}echo "<p>$tips</p>";}else{if(is_uploaded_file($file['tmp_name'])){$allow = ['jpg','jpeg','png','gif'];//! pathinfo:返回文件路径的信息,//!如果没有传入 options ，将会返回包括以下单元的数组 array：dirname，basename 和 extension$ext = pathinfo($file['name'])['extension'];// print_r($ext);//! in_array:检查数组中是否存在某个值if(in_array($ext,$allow)){// $path = 'C:\Users\Administrator\Desktop\后端学习质料\0427-1\up/';$path = 'C:/Users/Administrator/Desktop/后端学习质料/0427/ups/';//!将目标文件名md5加密$dest =$path . md5($file['name']) . '.' . $ext;$show = 'ups/'.md5($file['name']). '.' . $ext;// $dest =$name;// print_r($dest);//!move_uploaded_file: 将上传的文件移动到新位置if(move_uploaded_file($file['tmp_name'], $dest)){// move_uploaded_file($tmpName, $path);echo '<p style="color:red">上传成功</p>';echo "<img src='$show' width='200'>";}else{echo '<p style="color:lightblue">移动失败</p>';}}else{echo '<p style="color:lightblue">文件类型错误</p>';}}else{echo '<p style="color:lightblue">非法方式上传</p>';}}}?><head><meta charset="UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>多文件上传</title></head><body><form action="" method="post" enctype="multipart/form-data"><fieldset><legend>多文件上传</legend><input type="file" name="my_pic1"><input type="file" name="my_pic2"><input type="file" name="my_pic3"><button>上传</button></fieldset></form></body></html>
<?php//1.连接数据库$db = new PDO('mysql:dbname=php','root','root');//2.获取当前页,设置默认值为1.$now= $_GET['p']?? 1;//3.每页显示数量$num = 5;//4.获取数据库数据总条数$sql = 'SELECT count(`id`) as `total` from `student`';$stmt = $db ->prepare($sql);$stmt -> execute();//!bindColumn：绑定一列到一个 PHP 变量（类似于list()函数为变量赋值）$stmt ->bindColumn('total',$total);$stmt -> fetch(PDO::FETCH_ASSOC);//5.总页数//! ceil:向上取整$pages= ceil($total / $num);//6.偏移量$off= ($now - 1) * $num;//7.分页数据//!查询分页$sql = "SELECT * from `student` limit $num offset $off";$stmt = $db ->prepare($sql);$stmt -> execute();//读取所有分页里的数据$staffs = $stmt ->fetchAll(PDO::FETCH_ASSOC);//遍历并输出if(count($staffs)===0){echo '查询结果为空';}else{foreach($staffs as staff){extract($staff);printf('<pre>%d,%s,%s,%s</pre',$id,$name,$sex,$email);}}?><!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>分页页面</title></head><body><table><caption>学生信息表</caption><thead><tr><th>ID</th><th>姓名</th><th>性别</th><th>邮箱</th></tr></thead><tbody><?php foreach ($staffs as $staff) : extract($staff) ?><tr><td><?php echo $id ?></td><td><?php echo $name ?></td><td><?php echo $sex ?></td><td><?php echo $email ?></td></tr><?php endforeach ?></tbody></table><p><?php for($i = 1 ;$i <= $pages;$i++): ?><?php//!$_SERVER:服务器和执行环境信息,//!$_SERVER('PHP_SELF'):当前执行脚本的文件名$url = $_SERVER['PHP_SELF'] . '?p='.$i;$activa = $i == $_GET['p'] ? 'active' : null;?><a href="<?php echo $url ?>" class="<?php echo $activa ?>"><?php echo $i ?></a><?php endfor ?></p></body>