ftp_mkdir()

(PHP 4, PHP 5, PHP 7)

建立新目录

说明

ftp_mkdir(resource $ftp_stream,string $directory): string

在 FTP 服务器上建立一个目录名为参数$directory的新目录。

如果成功返回新建的目录名，否则返回FALSE。

参见ftp_rmdir()。

Here's the correct code for making recursive directories:
<?php
// function
function ftp_mksubdirs($ftpcon,$ftpbasedir,$ftpath){
  @ftp_chdir($ftpcon, $ftpbasedir); // /var/www/uploads
  $parts = explode('/',$ftpath); // 2013/06/11/username
  foreach($parts as $part){
   if(!@ftp_chdir($ftpcon, $part)){
     ftp_mkdir($ftpcon, $part);
     ftp_chdir($ftpcon, $part);
     //ftp_chmod($ftpcon, 0777, $part);
   }
  }
}
// usage
$path_of_storage = '/var/www/uploads';
$newftpdir = '2013/06/11/username';
$conn_id = ftp_connect($ftpserver);
ftp_login($conn_id, $login, $pass);
ftp_mksubdirs($conn_id,$path_of_storage,$newftpdir);
ftp_close($conn_id);
?>

if(!@ftp_chdir($ftpcon, $part)){
     ftp_mkdir($ftpcon, $part);
     ftp_chdir($ftpcon, $part);
     //ftp_chmod($ftpcon, 0777, $part);
   }
This if part of answer below, if you want working chmod you need to replace it with:
   if(!@ftp_chdir($ftpcon, $part)){
     ftp_mkdir($ftpcon, $part);
     ftp_chmod($ftpcon, 0777, $part);
     ftp_chdir($ftpcon, $part);
   }

For recurrent following function work better.
Some ftp servers (like WarFTP) become demented if you'll
try mkdir not from root dir and if path will be relative. 
The second if one of dir (like '/') already exist You'll get access denied. 
<?php
 function MkDir($path)
 {
  $dir=split("/", $path);
  $path="";
  $ret = true;
  
  for ($i=0;$i<count($dir);$i++)
  {
    $path.="/".$dir[$i];
    echo "$path\n";
    if(!@ftp_chdir($this->conn_id,$path)){
     @ftp_chdir($this->conn_id,"/");
     if(!@ftp_mkdir($this->conn_id,$path)){
     $ret=false;
     break;
     }
    } 
  }
  return $ret;
 }
?>

When trying to user the ftp_mkdir, or ftp_chdir I've noticed that some servers like the entire path such as
/usr/local/home/username/sitename/directory/
and other servers, want you to use the path from the initial login, such as just /sitename/directory/
Just wanted to pass this on

Updated and correct code for making recursive directories:
/**
 * A function to create ftp directories recursively.
 *
 * @param   $ftpcon the ftp connection resource
 * @param   $baseDir
 * @param   $path
 * @param int $mode
 * @return bool
 */   
function ftp_mksubdirs($ftpcon, $baseDir, $path, $mode = 0775) {
  $path = dirname($path);
  if ($baseDir !== DIRECTORY_SEPARATOR && strpos($path, $baseDir) !== false) {
    if (empty($path)) {
      // $baseDir equals to $path, it can only mean that this folder already exists
      return false;
    }
    if ($path[0] == DIRECTORY_SEPARATOR) {
      $path = substr($path, 1);
    }
  } else {
    if ($path[0] == DIRECTORY_SEPARATOR) {
      $path = substr($path, 1);
    }
  }
  @ftp_chdir($ftpcon, $baseDir);
  $parts  = explode(DIRECTORY_SEPARATOR, $path);
  $created = [];
  foreach ($parts as $part) {
    if (!@ftp_chdir($ftpcon, $part)) {
      $createdDir = @ftp_mkdir($ftpcon, $part);
      if ($createdDir !== false) {
        ftp_chmod($ftpcon, $mode, $createdDir);
      }
      $created[] = $createdDir;
      @ftp_chdir($ftpcon, $part);
    }
  }
  return !in_array(false, $created);
}