Formatter Helper

Formatter Helper

The Formatter helper provides functions to format the output with colors. You can do more advanced things with this helper than you can in How to Color and Style the Console Output.

The Symfony\Component\Console\Helper\FormatterHelper is included in the default helper set and you can get it by calling [getHelper()](https://github.com/symfony/symfony/blob/4.4/src/Symfony/Component/Console/Command/Command.php "Symfony\Component\Console\Command\Command::getHelper()"):

  1. $formatter = $this->getHelper('formatter');

The methods return a string, which you’ll usually render to the console by passing it to the [OutputInterface::writeln](https://github.com/symfony/symfony/blob/4.4/src/Symfony/Component/Console/Output/OutputInterface.php "Symfony\Component\Console\Output\OutputInterface::writeln()") method.

Print Messages in a Section

Symfony offers a defined style when printing a message that belongs to some “section”. It prints the section in color and with brackets around it and the actual message to the right of this. Minus the color, it looks like this:

  1. [SomeSection] Here is some message related to that section

To reproduce this style, you can use the [formatSection()](https://github.com/symfony/symfony/blob/4.4/src/Symfony/Component/Console/Helper/FormatterHelper.php "Symfony\Component\Console\Helper\FormatterHelper::formatSection()") method:

  1. $formattedLine = $formatter->formatSection(
  2. 'SomeSection',
  3. 'Here is some message related to that section'
  4. );
  5. $output->writeln($formattedLine);

Print Messages in a Block

Sometimes you want to be able to print a whole block of text with a background color. Symfony uses this when printing error messages.

If you print your error message on more than one line manually, you will notice that the background is only as long as each individual line. Use the [formatBlock()](https://github.com/symfony/symfony/blob/4.4/src/Symfony/Component/Console/Helper/FormatterHelper.php "Symfony\Component\Console\Helper\FormatterHelper::formatBlock()") to generate a block output:

  1. $errorMessages = ['Error!', 'Something went wrong'];
  2. $formattedBlock = $formatter->formatBlock($errorMessages, 'error');
  3. $output->writeln($formattedBlock);

As you can see, passing an array of messages to the [formatBlock()](https://github.com/symfony/symfony/blob/4.4/src/Symfony/Component/Console/Helper/FormatterHelper.php "Symfony\Component\Console\Helper\FormatterHelper::formatBlock()") method creates the desired output. If you pass true as third parameter, the block will be formatted with more padding (one blank line above and below the messages and 2 spaces on the left and right).

The exact “style” you use in the block is up to you. In this case, you’re using the pre-defined error style, but there are other styles, or you can create your own. See How to Color and Style the Console Output.

Print Truncated Messages

Sometimes you want to print a message truncated to an explicit character length. This is possible with the [truncate()](https://github.com/symfony/symfony/blob/4.4/src/Symfony/Component/Console/Helper/FormatterHelper.php "Symfony\Component\Console\Helper\FormatterHelper::truncate()") method.

If you would like to truncate a very long message, for example, to 7 characters, you can write:

  1. $message = "This is a very long message, which should be truncated";
  2. $truncatedMessage = $formatter->truncate($message, 7);
  3. $output->writeln($truncatedMessage);

And the output will be:

  1. This is...

The message is truncated to the given length, then the suffix is appended to end of that string.

Negative String Length

If the length is negative, the number of characters to truncate is counted from the end of the string:

  1. $truncatedMessage = $formatter->truncate($message, -5);

This will result in:

  1. This is a very long message, which should be trun...

Custom Suffix

By default, the ... suffix is used. If you wish to use a different suffix, pass it as the third argument to the method. The suffix is always appended, unless truncate length is longer than a message and a suffix length. If you don’t want to use suffix at all, pass an empty string:

  1. $truncatedMessage = $formatter->truncate($message, 7, '!!'); // result: This is!!
  2. $truncatedMessage = $formatter->truncate($message, 7, ''); // result: This is
  3. $truncatedMessage = $formatter->truncate('test', 10);
  4. // result: test
  5. // because length of the "test..." string is shorter than 10

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.