一个项目需求要几百台电脑都有打印功能,本来是想用网络打印机的,后来发现没有网络打印机,就自己动手写一个打印类算了。
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)
class Wprint{ //收集打印代碼 private $data = array(); //處理打印代碼 private $handle; public function __construct() { header("Content-type:text/html;charsetutf-8"); $this->link(); //鏈接數據庫 $this->collect($_POST["username"],$_POST["content"],$_POST["ip"]); $this->handle(); } //鏈接數據庫 private function link() { $link = mysql_connect('localhost', 'root', '123456'); mysql_select_db('shen', $link); mysql_query('SET NAMES utf8'); } //收集打印代碼 private function collect($username,$content,$ip) { $code["username"] = $username; $code["content"] = $this->check($content); $code["ip"] = $ip; $code["state"] = 0; $code["priority"] = 0; array_push($this->data,$code);//數據節點入棧 } //處理打印代碼入庫 private function handle() { foreach($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) { $id = mysql_insert_id(); //獲取最近insert操作得到的ID echo "數據收集成功,正在排隊打印,排隊ID為".$id; $this->num($id); } else { echo "數據收集失敗,請3秒後再一次提交"; } } } //檢查傳人數據是否為空 private function check($string) { if(strlen($string) == 0 || $string == " ") { echo "數據收集失敗,打印內容為空"; exit; }else { return $string; } } //獲取打印排隊人數 private function num($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 ",您前面還有".$num."個人在排隊"; } //打印數據 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 "<script tyle=\"text/javascript\"> window.print(); </script>"; $id = $row["id"]; $sql = "update print set state=1 where id=".$id; mysql_query($sql); echo "打印處理完成"; }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。