获取MySQL中二进制存取的图片,只好输出第一张,不能循环输出?
获取MySQL中二进制存取的图片,只能输出第一张,不能循环输出??
图片是以二进制的形式存入数据库的,不用while循环还能在浏览器上输出第一张,用了之后,输出的是乱码,是不是在输出图片之前不能有任何输出??
查了很多,都没有效果,求高手指点
- PHP code
<!-- Code highlighting produced by Actipro CodeHighlighter (freeware) http://www.CodeHighlighter.com/ --> <?php require_once("conn.php"); $cover=$_POST['cover']; if($_POST['sub']){ header("Content-Type:image/jpeg",true); //以只读的方式打开二进制文件 $fp=fopen($cover,"rb"); $image=addslashes(fread($fp,filesize($cover))); $sql1="insert into phototest (id,photo) values('','$image')"; $insert=mysql_query($sql1,$conn); $sql2="select * from phototest"; $select=mysql_query($sql2,$conn); //$result=mysql_fetch_array($select); echo $result[1];//用一条语句能输出一张图片 ?>
------解决方案--------------------
还是那句话,Content-Type:image/jpeg 声明响应内容为字节流。而你的代码还输出了字符流,自然导致浏览器无法准确识别和转换。
想在浏览器端显示多个图片,就必须遵循HTML格式标准。img标签的src属性支持file:// http:// data:// 等各种协议,但就是不能直接填入图片字节流。
还是希望你别在这棵树上吊着。你用这种没有意义,不合常理的项目练手,不仅不会有收获,反而会让你越学越迷糊
------解决方案--------------------
先前我对流的理解也有问题,你有空可以看看正确的解释:
http://zh.wikipedia.org/zh/MIME Content-type所声明的Mime类型含义
如果content-type为image/jpeg 那么后面的响应内容都只能被理解为是一张jpeg格式的图片。
但若响应内容为text/html,浏览器会当做HTML文档来解析,HTML的标签各有其含义,img标签会被用做展示图片,而src属性则规定图片从哪里加载。
http:// 后跟url链接 规定从服务器上下载,这将另外发起一个请求
file:// 后跟文件地址 规定从本地文件系统上读取,这只能读取本地文件
data:// 后跟有特殊格式的文本 参见rfc2397协议

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