PHP实现打印类（实现队列排队打印）

作者：袖梨 2022-06-24

类实现想法是：先把要打印的数据都收集起来，在用js调用window打印函数。目前就使用于IE。

类提供打印排队功能。（PS,说白了就是一条一条读取数据）

代码如下

复制代码

class Wprint{
     //收集打印代码
     private $data = array();
     //处理打印代码
     private $handle;
     public function __construct()
    {
       header("Content-type:text/html;charsetutf-8");
       $this->link(); //链接数据库
       $this->collect($_POST["username"],$_POST["content"],$_POST["ip"]);
       $this->handle();
     }
      //链接数据库
      private function link()
     {
        $link = mysql_connect('localhost', 'root', '123456');
        mysql_select_db('shen', $link);
        mysql_query('SET NAMES utf8');
      }
      //收集打印代码
      private function collect($username,$content,$ip)
      {
         $code["username"] = $username;
         $code["content"] = $this->check($content);
         $code["ip"] = $ip;
         $code["state"] = 0;
         $code["priority"] = 0;
         array_push($this->data,$code);//数据节点入栈
      }
      //处理打印代码入库
      private function handle()
      {
        foreach($this->data as $value)
        {
$sql = "insert into print(username,content,ip,state,priority)
values('{$value["username"]}','{$value["content"]}',
'{$value["ip"]}','{$value["state"]}','{$value["priority"]}')";
          $query = mysql_query($sql);
          if($query)
          {
            $id = mysql_insert_id(); //获取最近insert操作得到的ID
            echo "数据收集成功,正在排队打印,排队ID为".$id;
            $this->num($id);
          }
          else
          {
           echo "数据收集失败,请3秒后再一次提交";
          }
        }
      }
       //检查传人数据是否为空
      private function check($string)
      {
        if(strlen($string) == 0 || $string == " ")
        {
          echo "数据收集失败,打印内容为空";
          exit;
        }else
        {
          return $string;
        }
      }
      //获取打印排队人数
      private function num($id)
      {
        $sql = "select id from print where state=0 and id<".$id." order by id asc";
        $query = mysql_query($sql);
        $num = mysql_num_rows($query);
        echo ",您前面还有".$num."个人在排队";
      }
      //打印数据
      public function Yprint()
      {
         $sql = "select id,content from print where state=0 order by id asc limit 1";
         $query = mysql_query($sql);
         $row = mysql_fetch_array($query);
         if(!empty($row["content"]))
         {
           echo "";
           $id = $row["id"];
           $sql = "update print set state=1 where id=".$id;
           mysql_query($sql);

           echo "打印处理完成";
         }else
         {
             echo $row["content"];
         }
      }
   }

思想很简单，收集数据再一个一个处理。这样就不仅解决了网络打印的问题，还避免了网络打印打印过程排队的问题