php php如何以kb为单位获取Web图像大小？
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php how to get web image size in kb?
提问by fish man
php how to get web image size in kb?
php如何以kb为单位获取Web图像大小？
getimagesizeonly get the width and height.
getimagesize只获取宽度和高度。
and filesizecaused waring.
并filesize造成waring.
$imgsize=filesize("http://static.adzerk.net/Advertisers/2564.jpg");
echo $imgsize;
Warning: filesize() [function.filesize]: stat failed for http://static.adzerk.net/Advertisers/2564.jpg
Warning: filesize() [function.filesize]: stat failed for http://static.adzerk.net/Advertisers/2564.jpg
Is there any other way to get a web image size in kb?
有没有其他方法可以以 kb 为单位获取网络图像大小？
回答by mario
Short of doing a complete HTTP request, there is no easy way:
没有做一个完整的 HTTP 请求，没有简单的方法：
$img = get_headers("http://static.adzerk.net/Advertisers/2564.jpg", 1);
print $img["Content-Length"];
You can likely utilize cURLhowever to send a lighter HEADrequest instead.
回答by Morgan Delaney
<?php
$file_size = filesize($_SERVER['DOCUMENT_ROOT']."/Advertisers/2564.jpg"); // Get file size in bytes
$file_size = $file_size / 1024; // Get file size in KB
echo $file_size; // Echo file size
?>
回答by Nicholas Kreidberg
That sounds like a permissions issue because filesize() should work just fine.
这听起来像是权限问题，因为 filesize() 应该可以正常工作。
Here is an example:
下面是一个例子：
php > echo filesize("./9832712.jpg");
1433719
Make sure the permissions are set correctly on the image and that the path is also correct. You will need to apply some math to convert from bytes to KB but after doing that you should be in good shape!
确保在图像上正确设置了权限并且路径也正确。您将需要应用一些数学运算才能将字节转换为 KB，但这样做之后您应该处于良好状态！
回答by Nick Pyett
Not sure about using filesize()for remote files, but there are good snippets on php.net though about using cURL.
不确定filesize()用于远程文件，但在 php.net 上有关于使用 cURL 的很好的片段。
回答by Sandeep Tawaniya
You can use also this function
您也可以使用此功能
<?php
$filesize=file_get_size($dir.'/'.$ff);
$filesize=$filesize/1024;// to convert in KB
echo $filesize;
function file_get_size($file) {
//open file
$fh = fopen($file, "r");
//declare some variables
$size = "0";
$char = "";
//set file pointer to 0; I'm a little bit paranoid, you can remove this
fseek($fh, 0, SEEK_SET);
//set multiplicator to zero
$count = 0;
while (true) {
//jump 1 MB forward in file
fseek($fh, 1048576, SEEK_CUR);
//check if we actually left the file
if (($char = fgetc($fh)) !== false) {
//if not, go on
$count ++;
} else {
//else jump back where we were before leaving and exit loop
fseek($fh, -1048576, SEEK_CUR);
break;
}
}
//we could make $count jumps, so the file is at least $count * 1.000001 MB large
//1048577 because we jump 1 MB and fgetc goes 1 B forward too
$size = bcmul("1048577", $count);
//now count the last few bytes; they're always less than 1048576 so it's quite fast
$fine = 0;
while(false !== ($char = fgetc($fh))) {
$fine ++;
}
//and add them
$size = bcadd($size, $fine);
fclose($fh);
return $size;
}
?>
回答by lockdown
回答by Ahmad Vaqas Khan
You can get the file size by using the get_headers() function. Use below code:
您可以使用 get_headers() 函数获取文件大小。使用以下代码：
$image = get_headers($url, 1);
$bytes = $image["Content-Length"];
$mb = $bytes/(1024 * 1024);
echo number_format($mb,2) . " MB";
