How to perform hash operation on files in php_PHP tutorial

How PHP performs hash operations on files

The details are as follows:

This code is very useful. If you download a file and the website provides a hash result, you can perform a hash operation on the file you downloaded to verify whether the downloaded file is correct.

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if(!empty($_FILES)){ if ($_FILES["file"]["error"] > 0){ switch($_FILES["file"]["error"]){ case 1: echo "Error: The uploaded file exceeds the upload_max_filesize directive in php.ini "; break; case 2: echo "Error: The uploaded file exceeds the MAX_FILE_SIZE directive that was specified in the HTML form. "; break; case 3: echo "Error: The uploaded file was only partially uploaded. "; break; case 4: echo "Error: No file was uploaded. "; break; case 6: echo "Error: Missing a temporary folder. "; break; case 7: echo "Error: Failed to write file to disk. "; break; case 8: echo "Error: A PHP extension stopped the file upload. "; break; default: echo "Unknown error occured. "; } } else { echo 'Upload: ' . $_FILES['file']['name'] . ' '; echo 'Type: ' . $_FILES['file']['type'] . ' '; echo 'Size: ' . (round($_FILES['file']['size'] / 1024, 2)) . ' Kb '; if(array_search($_POST['algo'], hash_algos())===false){ echo 'Unknown hashing algorithm requested. '; } else { echo 'Hashing Algorithm: '. $_POST['algo'] . ' '; $hash = hash_file($_POST['algo'], $_FILES['file']['tmp_name']); echo 'Calculated hash: ' . $hash . ' '; if($_POST['exphash']!=='none' && !empty($_POST['exphash'])){ echo 'Expected hash: ' . $_POST['exphash'] . ' '; echo ($hash==$_POST['exphash'])? 'Hash matched expected value.' : 'Hash did not match expected value.'; echo ' '; } } } ?> Again } else { ?> Filename: Expected hash(optional): Choose an algorithm (This is the list of all the available algorithms in your php installation) foreach(hash_algos() as $algo){ if($algo=='md5'){ echo "$algo "; } else { echo "$algo "; } } ?> } ?>

http://www.bkjia.com/PHPjc/978261.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/978261.htmlTechArticlephp对文件进行hash运算的方法 具体如下： 这段代码非常有用，如果你下载了一个文件，网站提供了hash结果，你可以对你下载下来的文件进行...