blocks|key|740785|text|文件名至少需要用引号括起来(作为字符串)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|740786|if+(file_exists('http://www.mydomain.com/images/'.$filename))+{
+…+}|code-block|syntax|javascript|740787|此外，还要确保$filename得到了正确的验证。然后，只有在你的PHP配置中激活了allow_url_fopen，它才能工作|offset|length|style|CODE|740788|entityMap|0|LINK|mutability|MUTABLE|url|http://php.net/filesystem.configuration#ini.allow-url-fopen^0|0|0|7|9|16|F|16|F|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@$I|X|J|Y|K|L]|$I|Z|J|10|K|L]]|9|@$I|11|J|12|1|13]]|A|$]]|$1|M|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]]]

You need the filename in quotation marks at least (as string):

<pre><code>if (file_exists('http://www.mydomain.com/images/'.$filename)) {
 … }
</code></pre>

Also, make sure <code>$filename</code> is properly validated. And then, it will only work when <a href="http://php.net/filesystem.configuration#ini.allow-url-fopen" rel="noreferrer"><code>allow_url_fopen</code></a> is activated in your PHP config

blocks|key|740888|text|if+(file_exists('http://www.mydomain.com/images/'.$filename))+{}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|740889|这对我不起作用。我这样做的方式是使用getimagesize。|unstyled|740890|$src+=+'http://www.mydomain.com/images/'.$filename;

if+(@getimagesize($src))+{|740891|请注意，'@‘表示如果图像不存在(在这种情况下，函数通常会抛出错误：getimagesize(http://www.mydomain.com/images/filename.png)+[function.getimagesize]:+failed)，它将返回false。|offset|length|style|CODE|740892|entityMap^0|0|0|0|Y|2H|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|R|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$B|C]]|$1|I|3|J|5|F|7|T|8|@$K|U|L|V|M|N]]|9|@]|A|$]]|$1|O|3|-4|5|F|7|W|8|@]|9|@]|A|$]]]|P|$]]

<pre><code>if (file_exists('http://www.mydomain.com/images/'.$filename)) {}
</code></pre>

This didn't work for me. The way I did it was using getimagesize.

<pre><code>$src = 'http://www.mydomain.com/images/'.$filename;

if (@getimagesize($src)) {
</code></pre>

Note that the '@' will mean that if the image does not exist (in which case the function would usually throw an error: <code>getimagesize(http://www.mydomain.com/images/filename.png) [function.getimagesize]: failed</code>) it will return false.

blocks|key|740745|text|试着这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|740746|$file+=+'/path/to/foo.txt';+//+'images/'.$file+(physical+path)

if+(file_exists($file))+{
++++echo+"The+file+$file+exists";
}+else+{
++++echo+"The+file+$file+does+not+exist";
}|code-block|syntax|javascript|740747|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Try like this:

<pre><code>$file = '/path/to/foo.txt'; // 'images/'.$file (physical path)

if (file_exists($file)) {
 echo "The file $file exists";
} else {
 echo "The file $file does not exist";
}
</code></pre>

blocks|key|741185|text|以下是检查文件是否存在的最简单方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|741186|if(is_file($filename)){
++++return+true;+//the+file+exist
}else{
++++return+false;+//the+file+does+not+exist
}|code-block|syntax|javascript|741187|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Here is the simplest way to check if a file exist:

<pre><code>if(is_file($filename)){
 return true; //the file exist
}else{
 return false; //the file does not exist
}
</code></pre>

blocks|key|524427|text|public+static+function+is_file_url_exists($url)+{
++++++++if+(@file_get_contents($url,+0,+NULL,+0,+1))+{
++++++++++++return+1;
++++++++}

++++++++return+0;+++++++++++
++++}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|524428|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>public static function is_file_url_exists($url) {
 if (@file_get_contents($url, 0, NULL, 0, 1)) {
 return 1;
 }

 return 0; 
 }
</code></pre>

blocks|key|524499|text|如果该文件位于您的本地域，则不需要放入完整的URL。仅文件的路径。如果文件位于不同的目录中，则需要在路径前面加上".“|type|unstyled|depth|inlineStyleRanges|entityRanges|data|524500|$file+=+'./images/image.jpg';
if+(file_exists($file))+{}|code-block|syntax|javascript|524501|经常会出现".“则会导致该文件显示为不存在，而实际上它确实存在。|524502|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

If the file is on your local domain, you don't need to put the full URL. Only the path to the file. If the file is in a different directory, then you need to preface the path with "."

<pre><code>$file = './images/image.jpg';
if (file_exists($file)) {}
</code></pre>

Often times the "." is left off which will cause the file to be shown as not existing, when it in fact does.

blocks|key|524591|text|您必须使用绝对路径来查看文件是否存在。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|524592|$abs_path+=+'/var/www/example.com/public_html/images/';
$file_url+=+'http://www.example.com/images/'+.+$filename;

if+(file_exists($abs_path+.+$filename))+{

++++echo+"The+file+exists.+URL:"+.+$file_url;

}+else+{

++++echo+"The+file+does+not+exist";

}|code-block|syntax|javascript|524593|如果你正在为CMS或PHP框架编写代码，那么据我所知，它们都定义了文档根路径的常量。|524594|例如，WordPress使用ABSPATH，它可以在全球范围内使用，使用您的代码和站点url处理服务器上的文件。|524595|Wordpress示例：|524596|$image_path+=+ABSPATH+.+'/images/'+.+$filename;
$file_url+=+get_site_url()+.+'/images/'+.+$filename;

if+(file_exists($image_path))+{

++++echo+"The+file+exists.+URL:"+.+$file_url;

}+else+{

++++echo+"The+file+does+not+exist";

}|524597|我在这里做了额外的工作:)。因为这段代码不需要太多的维护，而且非常可靠，所以我会把它写成if语句的缩写：|524598|$image_path+=+ABSPATH+.+'/images/'+.+$filename;
$file_url+=+get_site_url()+.+'/images/'+.+$filename;

echo+(file_exists($image_path))?'The+file+exists.+URL:'+.+$file_url:'The+file+does+not+exist';|524599|速记IF语句解释：|524600|$stringVariable+=+($trueOrFalseComaprison+>+0)?'String+if+true':'String+if+false';|524601|entityMap^0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|10|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|11|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|12|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|13|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|14|8|@]|9|@]|A|$]]|$1|Q|3|R|5|D|7|15|8|@]|9|@]|A|$E|F]]|$1|S|3|T|5|6|7|16|8|@]|9|@]|A|$]]|$1|U|3|V|5|D|7|17|8|@]|9|@]|A|$E|F]]|$1|W|3|-4|5|6|7|18|8|@]|9|@]|A|$]]]|X|$]]

You have to use absolute path to see if the file exists.

<pre><code>$abs_path = '/var/www/example.com/public_html/images/';
$file_url = 'http://www.example.com/images/' . $filename;

if (file_exists($abs_path . $filename)) {

 echo "The file exists. URL:" . $file_url;

} else {

 echo "The file does not exist";

}
</code></pre>

If you are writing for CMS or PHP framework then as far as I know all of them have defined constant for document root path. 

e.g WordPress uses ABSPATH which can be used globally for working with files on the server using your code as well as site url.

Wordpress example:

<pre><code>$image_path = ABSPATH . '/images/' . $filename;
$file_url = get_site_url() . '/images/' . $filename;

if (file_exists($image_path)) {

 echo "The file exists. URL:" . $file_url;

} else {

 echo "The file does not exist";

}
</code></pre>

I'm going an extra mile here :). Because this code would no need much maintenance and pretty solid, I would write it with as shorthand if statement:

<pre><code>$image_path = ABSPATH . '/images/' . $filename;
$file_url = get_site_url() . '/images/' . $filename;

echo (file_exists($image_path))?'The file exists. URL:' . $file_url:'The file does not exist';
</code></pre>

Shorthand IF statement explained:

<pre><code>$stringVariable = ($trueOrFalseComaprison &gt; 0)?'String if true':'String if false';
</code></pre>

blocks|key|524659|text|您可以使用cURL。你可以让cURL只给你头部，而不是主体，这可能会让它更快。坏的域总是需要一段时间，因为您将等待请求超时；您可能可以使用cURL更改超时长度。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|524660|下面是一个例子：|524661|function+remoteFileExists($url)+{
$curl+=+curl_init($url);

//don't+fetch+the+actual+page,+you+only+want+to+check+the+connection+is+ok
curl_setopt($curl,+CURLOPT_NOBODY,+true);

//do+request
$result+=+curl_exec($curl);

$ret+=+false;

//if+request+did+not+fail
if+($result+!==+false)+{
++++//if+request+was+ok,+check+response+code
++++$statusCode+=+curl_getinfo($curl,+CURLINFO_HTTP_CODE);++

++++if+($statusCode+==+200)+{
++++++++$ret+=+true;+++
++++}
}

curl_close($curl);

return+$ret;
}
$exists+=+remoteFileExists('http://stackoverflow.com/favicon.ico');
if+($exists)+{
echo+'file+exists';
}+else+{
+++echo+'file+does+not+exist';+++
}|code-block|syntax|javascript|524662|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

you can use cURL. You can get cURL to only give you the headers, and not the body, which might make it faster. A bad domain could always take a while because you will be waiting for the request to time-out; you could probably change the timeout length using cURL.

Here is example: 

<pre><code>function remoteFileExists($url) {
$curl = curl_init($url);

//don't fetch the actual page, you only want to check the connection is ok
curl_setopt($curl, CURLOPT_NOBODY, true);

//do request
$result = curl_exec($curl);

$ret = false;

//if request did not fail
if ($result !== false) {
 //if request was ok, check response code
 $statusCode = curl_getinfo($curl, CURLINFO_HTTP_CODE); 

 if ($statusCode == 200) {
 $ret = true; 
 }
}

curl_close($curl);

return $ret;
}
$exists = remoteFileExists('http://stackoverflow.com/favicon.ico');
if ($exists) {
echo 'file exists';
} else {
 echo 'file does not exist'; 
}
</code></pre>

blocks|key|524344|text|您可以使用file_get_contents函数访问远程文件。详情请参见http://php.net/manual/en/function.file-get-contents.php。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|524345|entityMap|0|LINK|mutability|MUTABLE|url|http://php.net/manual/en/function.file-get-contents.php^0|5|H|10|1J|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@$9|O|A|P|B|C]]|D|@$9|Q|A|R|1|S]]|E|$]]|$1|F|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|G|$H|$5|I|J|K|E|$L|M]]]]

You can use the <code>file_get_contents</code> function to access remote files. See <a href="http://php.net/manual/en/function.file-get-contents.php" rel="nofollow">http://php.net/manual/en/function.file-get-contents.php</a> for details.

blocks|key|741200|text|试试这个：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|741201|if+(file_exists(FCPATH+.+'uploads/pages/'+.+$image))+{
++++unlink(FCPATH+.+'uploads/pages/'+.+$image);
}|code-block|syntax|javascript|741202|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

try this : 

<pre><code>if (file_exists(FCPATH . 'uploads/pages/' . $image)) {
 unlink(FCPATH . 'uploads/pages/' . $image);
}
</code></pre>

blocks|key|524917|text|如果您使用的是curl，可以尝试使用以下脚本：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|524918|function+checkRemoteFile($url)
{
++$ch+=+curl_init();
++curl_setopt($ch,+CURLOPT_URL,$url);
+//+don't+download+content
curl_setopt($ch,+CURLOPT_NOBODY,+1);
curl_setopt($ch,+CURLOPT_FAILONERROR,+1);
curl_setopt($ch,+CURLOPT_RETURNTRANSFER,+1);
if(curl_exec($ch)!==FALSE)
{
++++return+true;
}
else
{
++++return+false;
}|code-block|syntax|javascript|524919|}|524920|参考网址：https://hungred.com/how-to/php-check-remote-email-url-image-link-exist/|offset|length|524921|entityMap|0|LINK|mutability|MUTABLE|url|https://hungred.com/how-to/php-check-remote-email-url-image-link-exist/^0|0|0|0|5|1Z|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|X|8|@]|9|@$K|Y|L|Z|1|10]]|A|$]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]]]

<h1>If you are using curl, you can try the following script:</h1>

<pre><code>function checkRemoteFile($url)
{
 $ch = curl_init();
 curl_setopt($ch, CURLOPT_URL,$url);
 // don't download content
curl_setopt($ch, CURLOPT_NOBODY, 1);
curl_setopt($ch, CURLOPT_FAILONERROR, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
if(curl_exec($ch)!==FALSE)
{
 return true;
}
else
{
 return false;
}
</code></pre>

}

Reference URL: <a href="https://hungred.com/how-to/php-check-remote-email-url-image-link-exist/" rel="nofollow noreferrer">https://hungred.com/how-to/php-check-remote-email-url-image-link-exist/</a>

blocks|key|741539|text|如果您的图像的路径是相对于应用程序根目录的，最好使用如下所示的内容：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|741540|function+imgExists($path)+{
++++$serverPath+=+$_SERVER['DOCUMENT_ROOT']+.+$path;

++++return+is_file($serverPath)
++++++++&&+file_exists($serverPath);
}|code-block|syntax|javascript|741541|此函数的使用示例：|741542|$path+=+'/tmp/teacher_photos/1546595125-IMG_14112018_160116_0.png';

$exists+=+imgExists($path);

if+($exists)+{
++++var_dump('Image+exists.+Do+something...');
}|741543|我认为创建一些类似库的东西来检查适用于不同情况的图像是否存在是一个好主意。上面有很多很好的答案，你可以用来解决这个问题。|741544|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

If path to your image is relative to the application root it is better to use something like this:

<pre><code>function imgExists($path) {
 $serverPath = $_SERVER['DOCUMENT_ROOT'] . $path;

 return is_file($serverPath)
 &amp;&amp; file_exists($serverPath);
}
</code></pre>

Usage example for this function:

<pre><code>$path = '/tmp/teacher_photos/1546595125-IMG_14112018_160116_0.png';

$exists = imgExists($path);

if ($exists) {
 var_dump('Image exists. Do something...');
}
</code></pre>

I think it is good idea to create something like library to check image existence applicable for different situations. Above lots of great answers you can use to solve this task.

blocks|key|525133|text|这里有一个我用来检查任何类型的URL的函数。它将检查响应代码URL是否存在。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|525134|/*
+*+Check+is+URL+exists
+*
+*+@param++$url+++++++++++Some+URL
+*+@param++$strict++++++++You+can+add+it+true+to+check+only+HTTP+200+Response+code
+*++++++++++++++++++++++++or+you+can+add+some+custom+response+code+like+302,+304+etc.
+*
+*+@return+string+or+NULL
+*/
function+is_url_exists($url,+$strict+=+false)
{
++++if+(is_int($strict)+&&+$strict+>=+100+&&+$strict+<+600+%7C%7C+is_array($strict))+{
++++++++if(is_array($strict))+{
++++++++++++$response+=+$strict;
++++++++}+else+{
++++++++++++$response+=+[$strict];
++++++++}
++++}+else+if+($strict+===+true+%7C%7C+$strict+===+1)+{
++++++++$response+=+[200];
++++}+else+{
++++++++$response+=+[200,202,301,302,303];
++++}
++++$ch+=+curl_init();
++++curl_setopt($ch,+CURLOPT_URL,$url);
++++curl_setopt($ch,+CURLOPT_NOBODY,+1);
++++curl_setopt($ch,+CURLOPT_FAILONERROR,+1);
++++curl_setopt($ch,+CURLOPT_RETURNTRANSFER,+1);
++++$return+=+curl_exec($ch);
++++if+(!curl_errno($ch)+&&+$return+!==+false)+{
++++++++return+(+in_array(curl_getinfo($ch,+CURLINFO_HTTP_CODE),+$response)+!==+false+);
++++}
++++return+false;
}|code-block|syntax|javascript|525135|这正是您所需要的。|525136|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Here is one function that I use to check any kind of URL. It will check response code is URL exists or not.
<pre><code>/*
 * Check is URL exists
 *
 * @param $url Some URL
 * @param $strict You can add it true to check only HTTP 200 Response code
 * or you can add some custom response code like 302, 304 etc.
 *
 * @return string or NULL
 */
function is_url_exists($url, $strict = false)
{
 if (is_int($strict) &amp;&amp; $strict &gt;= 100 &amp;&amp; $strict &lt; 600 || is_array($strict)) {
 if(is_array($strict)) {
 $response = $strict;
 } else {
 $response = [$strict];
 }
 } else if ($strict === true || $strict === 1) {
 $response = [200];
 } else {
 $response = [200,202,301,302,303];
 }
 $ch = curl_init();
 curl_setopt($ch, CURLOPT_URL,$url);
 curl_setopt($ch, CURLOPT_NOBODY, 1);
 curl_setopt($ch, CURLOPT_FAILONERROR, 1);
 curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
 $return = curl_exec($ch);
 if (!curl_errno($ch) &amp;&amp; $return !== false) {
 return ( in_array(curl_getinfo($ch, CURLINFO_HTTP_CODE), $response) !== false );
 }
 return false;
}
</code></pre>
This is exactly what you need.

blocks|key|524371|text|使用fopen()和fread()从HTTP读取前5个字节，然后使用以下命令：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|524372|DEFINE("GIF_START","GIF");
DEFINE("PNG_START",pack("C",0x89)."PNG");
DEFINE("JPG_START",pack("CCCCCC",0xFF,0xD8,0xFF,0xE0,0x00,0x10));+|code-block|syntax|javascript|524373|来检测图像。|524374|entityMap^0|2|7|A|7|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|N|$]]

Read first 5 bytes form HTTP using <code>fopen()</code> and <code>fread()</code> then use this:

<pre><code>DEFINE("GIF_START","GIF");
DEFINE("PNG_START",pack("C",0x89)."PNG");
DEFINE("JPG_START",pack("CCCCCC",0xFF,0xD8,0xFF,0xE0,0x00,0x10)); 
</code></pre>

to detect image.

blocks|key|524796|text|file_exists不仅可以读取文件，还可以读取路径。因此，当$filename为空时，该命令将像这样运行：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|524797|file_exists("http://www.example.com/images/")|code-block|syntax|javascript|524798|如果/images/目录存在，该函数仍将返回true。|524799|我通常是这样写的：|524800|//+!empty($filename)+is+to+prevent+an+error+when+the+variable+is+not+defined
if+(!empty($filename)+&&+file_exists("http://www.example.com/images/$filename"))
{
++++//+do+something
}
else
{
++++//+do+other+things
}|524801|entityMap^0|0|B|W|9|0|0|M|4|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|11|8|@]|D|@]|E|$]]|$1|O|3|P|5|H|7|12|8|@]|D|@]|E|$I|J]]|$1|Q|3|-4|5|6|7|13|8|@]|D|@]|E|$]]]|R|$]]

<code>file_exists</code> reads not only files, but also paths. so when <code>$filename</code> is empty, the command would run as if it's written like this:

<pre><code>file_exists("http://www.example.com/images/")
</code></pre>

if the directory /images/ exists, the function will still return <code>true</code>.

I usually write it like this:

<pre><code>// !empty($filename) is to prevent an error when the variable is not defined
if (!empty($filename) &amp;&amp; file_exists("http://www.example.com/images/$filename"))
{
 // do something
}
else
{
 // do other things
}
</code></pre>

blocks|key|524869|text|对于目录和完整的文件路径，file_exists($filepath)将返回true结果，因此当没有传递文件名时，并不总是一个解决方案。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|524870|对于完整的文件路径，is_file($filepath)将仅返回true|524871|entityMap^0|D|M|0|A|I|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|P|8|@]|D|@]|E|$]]]|I|$]]

<code>file_exists($filepath)</code> will return a true result for a directory and full filepath, so is not always a solution when a filename is not passed.

<code>is_file($filepath)</code> will only return true for fully filepaths

blocks|key|741468|text|您需要使用file_exists的服务器路径|type|unstyled|depth|inlineStyleRanges|entityRanges|data|741469|例如|741470|if+(file_exists('/httpdocs/images/'.$filename))+{echo+'File+exist';+}|code-block|syntax|javascript|741471|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

you need server path with file_exists

for example

<pre><code>if (file_exists('/httpdocs/images/'.$filename)) {echo 'File exist'; }
</code></pre>

blocks|key|525082|text|if(@getimagesize($image_path)){
+...}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|525083|对我来说很有效。|unstyled|525084|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>if(@getimagesize($image_path)){
 ...}
</code></pre>

Is working for me.

blocks|key|741687|text|试试看：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|741688|$imgFile+=+'http://www.yourdomain.com/images/'.$fileName;
if+(is_file($imgFile)+&&+file_exists($imgFile))+{
++++echo+'File+exists';
}+else+{
++++echo+'File+not+exist';
}|code-block|syntax|javascript|741689|另一种方式：|741690|$imgFile+=+'http://www.yourdomain.com/images/'.$fileName;
if+(is_file($imgFile))+{.....
}|741691|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Try it:
<pre><code>$imgFile = 'http://www.yourdomain.com/images/'.$fileName;
if (is_file($imgFile) &amp;&amp; file_exists($imgFile)) {
 echo 'File exists';
} else {
 echo 'File not exist';
}
</code></pre>
Another Way:
<pre><code>$imgFile = 'http://www.yourdomain.com/images/'.$fileName;
if (is_file($imgFile)) {.....
}
</code></pre>

I need to see if a specific image exists on my cdn.

I've tried the following and it doesn't work:

<pre><code>if (file_exists(http://www.example.com/images/$filename)) {
 echo "The file exists";
} else {
 echo "The file does not exist";
}
</code></pre>

Even if the image exists or doesn't exist, it always says "The file exists". I'm not sure why its not working...

PHP: How to check if image file exists?

服务器

WordPress

我需要查看我的cdn上是否存在特定的镜像。我尝试过以下几种方法，但都不起作用：if (file_exists(http://www.example.com/images/$filename)) {    echo "The file exists";} else {    echo "The file does not exist";}即使图像存在或不存在，它也总是显示“文件存在”。我不知道为什么

问PHP:如何检查图片文件是否存在？
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回答 19

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问PHP:如何检查图片文件是否存在？EN

回答 19

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问PHP:如何检查图片文件是否存在？
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