php PHP片段

Posted 2021-05-05

<?php
/* creates a compressed zip file */
function create_zip($files = array(),$destination = '',$overwrite = true) {
    //if the zip file already exists and overwrite is false, return false
    if(file_exists($destination) && !$overwrite) { return false; }
    //vars
    $valid_files = array();
    //if files were passed in...
    if (is_array($files)) {
        //cycle through each file
        foreach($files as $file) {
            //make sure the file exists
            if(file_exists($file)) {
                $valid_files[] = $file;
            }
        }
    }
    //if we have good files...
    if(count($valid_files)) {
        //create the archive
        $zip = new ZipArchive();
        if($zip->open($destination,$overwrite ? ZIPARCHIVE::OVERWRITE : ZIPARCHIVE::CREATE) !== true) {
            return false;
        }
        //add the files
        foreach($valid_files as $file) {
            $zip->addFile($file,$file);
        }
        //debug
        //echo 'The zip archive contains ',$zip->numFiles,' files with a status of ',$zip->status;

        //close the zip -- done!
        $zip->close();

        //check to make sure the file exists
        return file_exists($destination);
    } else {
        return false;
    }
}



$files_to_zip = array(
    'upload/1_3266_671641323389_14800358_42187034_1524052_n.jpg', 'upload/1_3266_671641328379_14800358_42187035_3071342_n.jpg'
);
//if true, good; if false, zip creation failed
$zip_name = 'my-archive.zip';
$result = create_zip($files_to_zip,$zip_name);

if($result){
    header('Content-Type: application/zip');
    header('Content-disposition: attachment; filename=filename.zip');
    header('Content-Length: ' . filesize($zip_name));
    readfile($zip_name);
}
?>

// Set variable
$var = true;	// false = false
$var = 1;		// 0 = false
$var = "a";		// "" = false

// Return true if variable is greater than 0
//
// Case 1 - Faster and higher performence
//
echo ($var ? “true” : “false”);

// Case 2
//
($var) ? print “True” : print “False”;