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CSV

Charset conversion

The CharsetConverter class converts your CSV records using the mbstring extension and its supported character encodings.

Settings

public CharsetConverter::inputEncoding(string $input_encoding): self
public CharsetConverter::outputEncoding(string $output_encoding): self

The inputEncoding and outputEncoding methods set the object encoding properties. By default, the input encoding and the output encoding are set to UTF-8.

When building a CharsetConverter object, the methods do not need to be called in any particular order, and may be called multiple times. Because the CharsetConverter is immutable, each time its setter methods are called they return a new object without modifying the current one.

If the submitted charset is not supported by the mbstring extension an OutOfRangeException will be thrown.

Conversion

public CharsetConverter::convert(iterable $records): iterable

CharsetConverter::convert converts the collection of records according to the encoding settings.

use League\Csv\CharsetConverter;

$csv = new SplFileObject('/path/to/french.csv', 'r');
$csv->setFlags(SplFileObject::READ_CSV | SplFileObject::SKIP_EMPTY);

$encoder = (new CharsetConverter())->inputEncoding('iso-8859-15');
$records = $encoder->convert($csv);

The resulting data is converted from iso-8859-15 to the default UTF-8 since no output encoding charset was set using the CharsertConverter::outputEncoding method.

CharsetConverter as a Writer formatter

public CharsetConverter::__invoke(array $record): array

Using the CharsetConverter::__invoke method, you can register a CharsetConverter object as a record formatter using the Writer::addFormatter method.

use League\Csv\CharsetConverter;
use League\Csv\Writer;

$encoder = (new CharsetConverter())
    ->inputEncoding('utf-8')
    ->outputEncoding('iso-8859-15')
;

$writer = Writer::createFromPath('/path/to/your/csv/file.csv');
$writer->addFormatter($encoder);

$writer->insertOne(["foo", "bébé", "jouet"]);
//all 'utf-8' characters are now automatically encoded into 'iso-8859-15' charset

CharsetConverter as a PHP stream filter

public static CharsetConverter::addTo(AbstractCsv $csv, string $input_encoding, string $output_encoding): AbstractCsv
public static CharsetConverter::register(): void
public static CharsetConverter::getFiltername(string $input_encoding, string $output_encoding): string

Usage with CSV objects

If your CSV object supports PHP stream filters then you can use the CharsetConverter class as a PHP stream filter using the library stream filtering mechanism instead.

The CharsetConverter::addTo static method:

  • registers the CharsetConverter class under the generic filtername convert.league.csv.* if it is not registered yet;
  • configures the stream filter using the supplied parameters;
  • adds the configured stream filter to the submitted CSV object;
use League\Csv\CharsetConverter;
use League\Csv\Writer;

$writer = Writer::createFromPath('/path/to/your/csv/file.csv');
CharsetConverter::addTo($writer, 'utf8', 'iso-8859-15');

$writer->insertOne(["foo", "bébé", "jouet"]);
//all 'utf-8' characters are now automatically encoded into 'iso-8859-15' charset

Usage with PHP stream resources

To use this stream filter outside League\Csv objects you need to:

  • register the stream filter using CharsetConverter::register method.
  • use CharsetConverter::getFiltername with one of PHP’s attaching stream filter functions with the correct arguments as shown below:
use League\Csv\CharsetConverter;

CharsetConverter::register();

$resource = fopen('/path/to/my/file', 'r');
$filter = stream_filter_append(
    $resource,
    CharsetConverter::getFiltername('utf-8', 'iso-8859-15'),
    STREAM_FILTER_READ
);

while (false !== ($record = fgetcsv($resource))) {
    //$record is correctly encoded
}

If your system supports the iconv extension you should use PHP's built in iconv stream filters instead for better performance.

available since version 9.22.0

When not mentioned, PHP will register the stream filter twice as a stream filter that can be used on read and as a stream filter that can be used on write. This behaviour may introduce subtle issues if you are not aware of that behaviour. To avoid such scenario we are introducing the following more strict methods:

  • CharsetConverter::appendOnReadTo,
  • CharsetConverter::appendOnWriteTo,
  • CharsetConverter::prependOnReadTo,
  • CharsetConverter::prependOnWriteTo

To better convey when the conversion will happen. So if you only want to convert the resource on read you should use the following snippet

use League\Csv\CharsetConverter;

$resource = fopen('/path/to/my/file', 'r+');
$filter = CharsetConverter::appendOnReadTo($resource, 'utf-8', 'iso-8859-15');
echo stream_get_contents($resource); // the return string is converted from 'utf-8' to 'iso-8859-15'

Even if the resource is writable, the stream filter will only be used when the file is read

The appendTo and prependTo static methods that were introduced in version 9.17 are therefore deprecated as of version 9.22