PHP文件上传问题解析-优快云博客

本文链接：https://blog.youkuaiyun.com/StriveScript/article/details/6173608

客户端软件：upload.html

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>客户端</title> </head> <body> <table width=100%> <form action='http://teach.onlinewebshop.net/upload.php' method='post' enctype=multipart/form-data> <tr><td> </td><td width=30%> <input type=file name='upfile' size=40><br></td><td> </td></tr> <tr><td> </td><td width=30%> <input type=submit name='按键提交'></center></td><td> </td></tr> <form> </table> </body> </html>

服务端：upload.php

<?php //如果报错显示错误代码 if($_FILES['upfile']['error']>0){ echo "Error Number : ".$_FILES['upfile']['error']."<hr>"; } else{ //限制上传图片如果正确显示文件的信息 if(($_FILES['upfile']['type'] == "image/gif")||($_FILES['upfile']['type'] == "image/jpeg")||($_FILES['upfile']['type'] == "image/pjpeg")||($_FILES['upfile']['type'] == "image/png")&&($_FILES['upfile']['size'])<200000){ if(file_exists("./upload/".$_FILES['upfile']['name'])){ echo "File Allready Exists !!!<hr>"; } $filepath = "/upload/".$_FILES['upfile']['name']; else{ echo "File-name : ".$_FILES['upfile']['name']."<hr>"; echo "File-type : ".$_FILES['upfile']['type']."<hr>"; echo "File-size : ".$_FILES['upfile']['size']."<hr>"; echo "File-tmp_name : ".$_FILES['upfile']['tmp_name']."<hr>"; move_uploaded_file($_FILES['upfile']['tmp_name'],$filepath); } //显示图片 echo "<img src=".$filepath." mce_src=".$filepath." border=0 /><hr>"; } else{ echo "File type forbidden<hr>"; } } ?>`-

正确的返回包括文件信息，以及图片的展示

选择文件提交之后，返回一片空白！！！

分析错误

最终确定方案：

<?php //如果报错显示错误代码 if($_FILES['upfile']['error']>0){ echo "Error Number : ".$_FILES['upfile']['error']."<hr>"; } else{ //限制上传图片如果正确显示文件的信息 $filetype = $_FILES['upfile']['type']; $filepath = dirname(__FILE__)."/upload/".$_FILES['upfile']['name']; if(($filetype == "image/gif")||($filetype == "image/jpeg")||($filetype == "image/bmp")||($filetype == "image/pjpeg")||($filetype == "image/png")&&($_FILES['upfile']['size']<200000)){ echo "File-name : ".$_FILES['upfile']['name']."<hr>"; echo "File-type : ".$filetype."<hr>"; echo "File-size : ".$_FILES['upfile']['size']."byte<hr>"; echo "File-tmp_name : ".$_FILES['upfile']['tmp_name']."<hr>"; if(file_exists($filepath)){ echo "File Allready Exists !!!<hr>"; } else{ move_uploaded_file($_FILES['upfile']['tmp_name'],$filepath); echo dirname(__FILE__)."/upload/".$filepath."<hr>"; } //显示图片 echo "<hr><center><img src="/upload/" mce_src="upload/"".$_FILES['upfile']['name']." border=0 /></center><hr>"; } else{ echo "File type forbidden<hr>"; } } ?>

错误总结：
1、echo 输出显示的时候进行运算的问题？
2、move_loaded_file 目的文件夹使用绝对路径？相对路径？
3、细微语法错误，比如修改代码的时候双引号(")的残留!!!!

使用fopen/fwrite/move_loaded_file等的时候如果加入了路径，请注意是否具有读写权限，以及能否新建文件？能否新建文件夹！！！！