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 FormatterHelper
is included
in the default helper set, which you can get by calling
getHelperSet()
:
$formatter = $this->getHelper('formatter');
The methods return a string, which you’ll usually render to the console by
passing it to the
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()
method:
$formattedLine = $formatter->formatSection(
'SomeSection',
'Here is some message related to that section'
);
$output->writeln($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()
to generate a block output:
$errorMessages = ['Error!', 'Something went wrong'];
$formattedBlock = $formatter->formatBlock($errorMessages, 'error');
$output->writeln($formattedBlock);
As you can see, passing an array of messages to the
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()
method.
If you would like to truncate a very long message, for example, to 7 characters, you can write:
$message = "This is a very long message, which should be truncated";
$truncatedMessage = $formatter->truncate($message, 7);
$output->writeln($truncatedMessage);
And the output will be:
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:
$truncatedMessage = $formatter->truncate($message, -5);
This will result in:
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:
$truncatedMessage = $formatter->truncate($message, 7, '!!'); // result: This is!!
$truncatedMessage = $formatter->truncate($message, 7, ''); // result: This is
$truncatedMessage = $formatter->truncate('test', 10);
// result: test
// because length of the "test..." string is shorter than 10