第六节 常用库函数
1时间和日期
//获取时间 1430376419
echo timeecho '<br>'// 时区 Europe/Berlin
echo // 设置时区
echo 'Asia/Shanghai'//获取日期 2015-04-30 08-04-18
echo date'Y-m-d H:i:s'echo date 'Y-m-d H:i:s'time());
2JSON格式数据的操作
/* JSON format [1,2,5,7,8,'Hello',[6,7,8]] {"h":"Hello","w":"World"} */ //编码 $arr = array(1,2,5,8,'hello', 'Xueyuan',array('h'=>"Hello",'name'=>'xueyuang')); print_r($arr); echo json_encode($arr); echo '<br>'; $obj = array('h'=>"Hello",'w'=>'Word', array(3,2,1)); echo json_encode($obj); //解码 $jsonStr = '{"h":"Hello","w":"Word","0":[3,2,1]}'; $obj = json_decode($jsonStr); print_r($obj); //访问某元素 echo $obj->h;
3文件操作
//write data 返回文件的标识 以@开发,如果遇到警告则忽略 $f = fopen('data','w'); if($f) { fwrite($f, 'Hello php'); fclose($f); echo 'ok'; }else{ echo '创建文件失败'; } echo '<br>'; //read data $f = fopen('data','r'); while(!feof($f)) { $content = fgets($f); echo $content; } fclose($f); // get content echo file_get_contents('data');
4生成图片
//创建图片 $img = imagecreate(400,300); //创建图片背景色 imagecolorallocate($img,255,255,255); imageellipse($img,200,200,50,50,imagecolorallocate($img,255,0,0)); //输出图片文本 header('Content-type:image/png'); imagepng($img);
5图片打水印
$img = imagecreatefromjpeg("a.jpg"); imagestring($img,2,5,5,"jacksun",imagecolorallocate($img,255,255,0) ); header('Content-type:image/jpeg'); imagejpeg($img);