PHP 如果文件存在
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PHP if file exists
提问by
Here is my code.
这是我的代码。
$filename = "$myMedia catalog/category/ $myImage.png";
$filename = str_replace(" ", "", $filename);
if (file_exists($filename)) {
echo "The file $filename exists";
} else {
echo "The file $filename does not exist";
}
The variableabove outputs http://50.87.6.244/~storeupp/media/catalog/category/Game_Used.pngwhich does exist. However, it says that it does not exists.
的variable上述输出http://50.87.6.244/~storeupp/media/catalog/category/Game_Used.png其确实存在。但是，它说它不存在。
Any idea why?
知道为什么吗？
采纳答案by Vineet1982
Just try to use like this:
试着像这样使用：
$filename = dirname(__FILE__) . "/ $myMedia catalog/category/ $myImage.png";
$filename = str_replace(" ", "", $filename);
if (file_exists($filename)) {
echo "The file $filename exists";
} else {
echo "The file $filename does not exist";
}
回答by Michael
I don't know, but I think, the following code will be more successful if you have external web items as assets:
我不知道，但我认为，如果您将外部网络项目作为资产，以下代码会更成功：
$filename = $myMedia."catalog/category/".$myImage.".png";
$headers = @get_headers($filename);
$exists = ($file_headers[0] == 'HTTP/1.1 404 Not Found');
回答by user2410595
OT: Instead of using spaces and str_replace(" ", "", $filename) you can surround variable betwen "{}" brackets.
OT：您可以将变量括在“{}”括号之间，而不是使用空格和 str_replace(" ", "", $filename)。
$filename = "{$myMedia}catalog/category/{$myImage}.png";
$filename = "{$myMedia}catalog/category/{$myImage}.png";
回答by John Conde
That file looks like it is outside of your web root. As a result it is not available via the web. If you're trying to check a file that is local on your machine, use the file root instead. (i.e. /path/to/media/catalog/category/Game_Used.png)
该文件看起来像是在您的 Web 根目录之外。因此，它无法通过网络获得。如果您尝试检查计算机上的本地文件，请改用文件根目录。（即/path/to/media/catalog/category/Game_Used.png）
回答by Matt Busche
You need to reference the path to the file or the directory you cannot use http://links
您需要引用文件的路径或不能使用http://链接的目录
回答by christopher
In the documentationit states that the file_exists() function is only available with some URL wrappers as of PHP 5.0.
在文档中，它指出 file_exists() 函数仅适用于 PHP 5.0 的某些 URL 包装器。
