文件上传分为两个步骤
1,客户端用户上传;
a)需要一个表单域,用来注入要上传的文件,
<span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="file"</span> <span>/></span>
b)用户选择所需要上传的文件
c)用户点击,将文件发送给服务器
2,服务器接收
form表单使用POST提交方式。
*注意:GET,POST不能提交二进制文件,但是POST提交增加一个属性便可以完成。
<span><</span><span>form </span><span>action</span><span>="file.php"</span><span> method</span><span>="POST"</span><span> enctype</span><span>="multipart/form-data"</span><span>></span>
html部分: DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>文件上传title> head> <body> <span><</span><span>form </span><span>action</span><span>="file.php"</span><span> method</span><span>="POST"</span><span> enctype</span><span>="multipart/form-data"</span><span>></span> <span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="file"</span> <span>/></span> <input type="submit" value="提交"/> form> body>
var_dump($_FILES) 时发现得到的是一个数组
<span>array</span> 'file' => <span>array</span> 'name' => <span>string</span> '4.jpg' (length=5<span>) </span>'type' => <span>string</span> 'image/jpeg' (length=10<span>) </span>'tmp_name' => <span>string</span> 'F:\wamp\tmp\php904D.tmp' (length=23<span>) </span>'error' => int 0 'size' => int 273665
a)根据二维数组找到error点;
<span>switch</span>(<span>$_FILES</span>['file']['error'<span>]){ </span><span>case</span> '0': <span>echo</span> "上传成功"<span>; </span><span>break</span><span>; </span><span>case</span> '1': <span>case</span> '2': <span>header</span>('Refresh:3;url=file.html'<span>); </span><span>echo</span> "文件大小超过服务器限制"<span>; </span><span>break</span><span>; </span><span>case</span> '3': <span>header</span>('Refresh:3;url=file.html'<span>); </span><span>echo</span> "文件只有部分上传成功"<span>; </span><span>break</span><span>; </span><span>case</span> '4': <span>header</span>('Refresh:3;url=file.html'<span>); </span><span>echo</span> "未选中文件,请重新选择文件并提交"<span>; </span><span>break</span><span>; </span><span>default</span>: <span>echo</span> "文件上传失败"<span>; }</span>
b)文件上传成功后,放到了指定的临时目录中,此时需要更改到期待的文件中,
php有一个函数可以完成,move_uploaded_file()
eg:
<span>move_uploaded_file</span>(<span>$_FILES</span>['file']['tmp_name'], './cy1/' . <span>$_FILES</span>['file']['name']);
注:tmp_name,文件上传到服务器的临时目录,
'name',文件在客户端本地的文件名字。