Latte Filters
Filters are functions that change or format the data to a form we want. This is summary of the built-in filters which are available.
capitalize |
lower case, the first letter of each word upper case |
firstUpper |
makes the first letter upper case |
lower |
makes a string lower case |
upper |
makes a string upper case |
ceil |
rounds a number up to a given precision |
floor |
rounds a number down to a given precision |
round |
rounds a number to a given precision |
escapeUrl |
escapes parameter in URL |
noescape |
prints a variable without escaping |
query |
generates a query string in the URL |
There are also escaping filters for HTML (escapeHtml
and escapeHtmlComment
), XML
(escapeXml
), JavaScript (escapeJs
), CSS (escapeCss
) and iCalendar
(escapeICal
), which Latte uses itself thanks to context-aware escaping and you do not need to
write them.
checkUrl |
sanitizes string for use inside href attribute |
nocheck |
prevents automatic URL sanitization |
Latte the src
and href
attributes checks automatically, so you almost don't need to use the
checkUrl
filter.
All built-in filters work with UTF‑8 encoded strings.
Usage
Latte allows calling filters by using the pipe sign notation (preceding space is allowed):
<h1>{$heading|upper}</h1>
Filters can be chained, in that case they apply in order from left to right:
<h1>{$heading|lower|capitalize}</h1>
Parameters are put after the filter name separated by colon or comma:
<h1>{$heading|truncate:20,''}</h1>
Filters can be applied on expression:
{var $name = ($title|upper) . ($subtitle|lower)}</h1>
Custom filters can be registered this way:
$latte = new Latte\Engine;
$latte->addFilter('shortify', fn(string $s, int $len = 10) => mb_substr($s, 0, $len));
We use it in a template like this:
<p>{$text|shortify}</p>
<p>{$text|shortify:100}</p>
Filters
batch (int length, mixed item): array
Filter that simplifies the listing of linear data in the form of a table. It returns an array of array with the given number of items. If you provide a second parameter this is used to fill up missing items on the last row.
{var $items = ['a', 'b', 'c', 'd', 'e']}
<table>
{foreach ($items|batch: 3, 'No item') as $row}
<tr>
{foreach $row as $column}
<td>{$column}</td>
{/foreach}
</tr>
{/foreach}
</table>
Prints:
<table>
<tr>
<td>a</td>
<td>b</td>
<td>c</td>
</tr>
<tr>
<td>d</td>
<td>e</td>
<td>No item</td>
</tr>
</table>
breakLines
Inserts HTML line breaks before all newlines.
{var $s = "Text & with \n newline"}
{$s|breakLines} {* outputs "Text & with <br>\n newline" *}
bytes (int $precision=2)
Formats a size in bytes to human-readable form.
{$size|bytes} 0 B, 1.25 GB, …
{$size|bytes:0} 10 B, 1 GB, …
ceil (int $precision=0)
Rounds a number up to a given precision.
{=3.4|ceil} {* outputs 4 *}
{=135.22|ceil:1} {* outputs 135.3 *}
{=135.22|ceil:3} {* outputs 135.22 *}
capitalize
Returns a title-cased version of the value. Words will start with uppercase letters, all remaining characters are lowercase.
Requires PHP extension mbstring
.
{='i like LATTE'|capitalize} {* outputs 'I Like Latte' *}
See also firstUpper, lower, upper.
checkUrl
Enforces URL sanitization. It checks if the variable contains a web URL (ie. HTTP/HTTPS protocol) and prevents the writing of links that may pose a security risk.
{var $link = 'javascript:window.close()'}
<a data-href="{$link|checkUrl}">checked</a>
<a data-href="{$link}">unchecked</a>
Prints:
<a data-href="">checked</a>
<a data-href="javascript:window.close()">unchecked</a>
See also nocheck.
clamp (int|float min, int|float max)
Returns value clamped to the inclusive range of min and max.
{$level|clamp: 0, 255}
Also exists as function.
dataStream (string $mimetype=detect)
Converts the content to data URI scheme. It can be used to insert images into HTML or CSS without the need to link external files.
Lets have an image in a variable $img = Image::fromFile('obrazek.gif')
, then
<img src="{$img|dataStream}">
Prints for example:
<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUA
AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO
9TXL0Y4OHwAAAABJRU5ErkJggg==">
Requires PHP extension fileinfo
.
date (string format)
Returns a date in the given format using options of strftime or date PHP functions. Filter gets a date as a UNIX timestamp, a string or an object of
DateTime
type.
{$today|date:'%d.%m.%Y'}
{$today|date:'j. n. Y'}
escapeUrl
Escapes a variable to be used as a parameter in URL.
<a href="http://example.com/{$name|escapeUrl}">{$name}</a>
See also query.
explode (string
$separator=''
)
Splits a string by the given delimiter and returns an array of strings. Alias for split
.
{='one,two,three'|explode:','} {* returns ['one', 'two', 'three'] *}
If the delimiter is an empty string (default value), the input will be divided into individual characters:
{='123'|explode} {* returns ['1', '2', '3'] *}
You can use also alias split
:
{='1,2,3'|split:','} {* returns ['1', '2', '3'] *}
See also implode.
first
Returns the first element of array or character of string:
{=[1, 2, 3, 4]|first} {* outputs 1 *}
{='abcd'|first} {* outputs 'a' *}
floor (int $precision=0)
Rounds a number down to a given precision.
{=3.5|floor} {* outputs 3 *}
{=135.79|floor:1} {* outputs 135.7 *}
{=135.79|floor:3} {* outputs 135.79 *}
firstUpper
Converts a first letter of value to uppercase. Requires PHP extension mbstring
.
{='the latte'|firstUpper} {* outputs 'The latte' *}
See also capitalize, lower, upper.
implode (string $glue=''
)
Return a string which is the concatenation of the strings in the array. Alias for join
.
{=[1, 2, 3]|implode} {* outputs '123' *}
{=[1, 2, 3]|implode:'|'} {* outputs '1|2|3' *}
You can also use an alias join
:
{=[1, 2, 3]|join} {* outputs '123' *}
indent (int $level=1, string
$char="\t"
)
Indents a text from left by a given number of tabs or other characters which we specify in the second optional argument. Blank lines are not indented.
<div>
{block |indent}
<p>Hello</p>
{/block}
</div>
Prints:
<div>
<p>Hello</p>
</div>
last
Returns the last element of array or character of string:
{=[1, 2, 3, 4]|last} {* outputs 4 *}
{='abcd'|last} {* outputs 'd' *}
length
Returns length of a string or array.
- for strings, it will return length in UTF‑8 characters
- for arrays, it will return count of items
- for objects that implement the Countable interface, it will use the return value of the count()
- for objects that implement the IteratorAggregate interface, it will use the return value of the iterator_count()
{if ($users|length) > 10}
...
{/if}
lower
Converts a value to lowercase. Requires PHP extension mbstring
.
{='LATTE'|lower} {* outputs 'latte' *}
See also capitalize, firstUpper, upper.
nocheck
Prevents automatic URL sanitization. Latte automatically checks if the variable contains a web URL (ie. HTTP/HTTPS protocol) and prevents the writing of links that may pose a security risk.
If the link uses a different scheme, such as javascript:
or data:
, and you are sure of its contents,
you can disable the check via |nocheck
.
{var $link = 'javascript:window.close()'}
<a href="{$link}">checked</a>
<a href="{$link|nocheck}">unchecked</a>
Prints:
<a href="">checked</a>
<a href="javascript:window.close()">unchecked</a>
See also checkUrl.
noescape
Disables automatic escaping.
{var $trustedHtmlString = '<b>hello</b>'}
Escaped: {$trustedHtmlString}
Unescaped: {$trustedHtmlString|noescape}
Prints:
Escaped: <b>hello</b>
Unescaped: <b>hello</b>
Misuse of the noescape
filter can lead to an XSS vulnerability! Never use it unless you are
absolutely sure what you are doing and that the string you are printing comes from a trusted source.
number (int $decimals=0, string
$decPoint='.'
, string $thousandsSep=','
)
Formats a number to given number of decimal places. You can also specify a character of the decimal point and thousands separator.
{1234.20 |number} 1,234
{1234.20 |number:1} 1,234.2
{1234.20 |number:2} 1,234.20
{1234.20 |number:2, ',', ' '} 1 234,20
padLeft (int length, string
$pad=' '
)
Pads a string to a certain length with another string from left.
{='hello'|padLeft: 10, '123'} {* outputs '12312hello' *}
padRight (int length, string
$pad=' '
)
Pads a string to a certain length with another string from right.
{='hello'|padRight: 10, '123'} {* outputs 'hello12312' *}
query
Dynamically generates a query string in the URL:
<a href="http://example.com/?{[name: 'John Doe', age: 43]|query}">click</a>
<a href="http://example.com/?search={$search|query}">search</a>
Prints:
<a href="http://example.com/?name=John+Doe&age=43">click</a>
<a href="http://example.com/?search=Foo+Bar">search</a>
Keys with a value of null
are omitted.
See also escapeUrl.
random
Returns random element of array or character of string:
{=[1, 2, 3, 4]|random} {* example output: 3 *}
{='abcd'|random} {* example output: 'b' *}
repeat (int count)
Repeats the string x-times.
{='hello'|repeat: 3} {* outputs 'hellohellohello' *}
replace (string|array search, string
$replace=''
)
Replaces all occurrences of the search string with the replacement string.
{='hello world'|replace: 'world', 'friend'} {* outputs 'hello friend' *}
Multiple replacements can be made at once:
{='hello world'|replace: [h => l, l => h]} {* outputs 'lehho worhd' *}
replaceRE (string pattern, string
$replace=''
)
Replaces all occurrences according to regular expression.
{='hello world'|replaceRE: '/l.*/', 'l'} {* outputs 'hel' *}
reverse
Reverses given string or array.
{var $s = 'Nette'}
{$s|reverse} {* outputs 'etteN' *}
{var $a = ['N', 'e', 't', 't', 'e']}
{$a|reverse} {* returns ['e', 't', 't', 'e', 'N'] *}
round (int $precision=0)
Rounds a number to a given precision.
{=3.4|round} {* outputs 3 *}
{=3.5|round} {* outputs 4 *}
{=135.79|round:1} {* outputs 135.8 *}
{=135.79|round:3} {* outputs 135.79 *}
slice (int start, ?int $length=null, bool $preserveKeys=false)
Extracts a slice of an array or a string.
{='hello'|slice: 1, 2} {* outputs 'el' *}
{=['a', 'b', 'c']|slice: 1, 2} {* outputs ['b', 'c'] *}
The slice filter works as the array_slice
PHP function for arrays and mb_substr
for strings with a
fallback to iconv_substr
in UTF‑8 mode.
If the start is non-negative, the sequence will start at that start in the variable. If start is negative, the sequence will start that far from the end of the variable.
If length is given and is positive, then the sequence will have up to that many elements in it. If the variable is shorter than the length, then only the available variable elements will be present. If length is given and is negative then the sequence will stop that many elements from the end of the variable. If it is omitted, then the sequence will have everything from offset up until the end of the variable.
Filter will reorder and reset the integer array keys by default. This behaviour can be changed by setting preserveKeys to true. String keys are always preserved, regardless of this parameter.
sort
Filter that sorts an array and maintain index association.
{foreach ($names|sort) as $name}
...
{/foreach}
Array sorted in reverse order.
{foreach ($names|sort|reverse) as $name}
...
{/foreach}
You can pass your own comparison function as a parameter:
{var $sorted = ($names|sort: fn($a, $b) => $b <=> $a)}
spaceless
Removes unnecessary whitespace from the output. You can also use alias strip
.
{block |spaceless}
<ul>
<li>Hello</li>
</ul>
{/block}
Prints:
<ul> <li>Hello</li> </ul>
stripHtml
Converts HTML to plain text. That is, it removes HTML tags and converts HTML entities to text.
{='<p>one < two</p>'|stripHtml} {* outputs 'one < two' *}
The resulting plain text can naturally contain characters that represent HTML tags, for example
'<p>'|stripHtml
is converted to <p>
. Never output the resulting text with
|noescape
, as this may lead to a security vulnerability.
substr (int offset, ?int $length=null)
Extracts a slice of a string. This filter has been replaced by a slice filter.
{$string|substr: 1, 2}
trim (string
$charlist=" \t\n\r\0\x0B\u{A0}"
)
Strip leading and trailing characters, by default whitespace.
{=' I like Latte. '|trim} {* outputs 'I like Latte.' *}
{=' I like Latte.'|trim: '.'} {* outputs ' I like Latte' *}
truncate (int length, string
$append='…'
)
Shortens a string to the maximum given length but tries to preserve whole words. If the string is truncated it adds ellipsis at the end (this can be changed by the second parameter).
{var $title = 'Hello, how are you?'}
{$title|truncate:5} {* Hell… *}
{$title|truncate:17} {* Hello, how are… *}
{$title|truncate:30} {* Hello, how are you? *}
upper
Converts a value to uppercase. Requires PHP extension mbstring
.
{='latte'|upper} {* outputs 'LATTE' *}
See also capitalize, firstUpper, lower.
webalize
Converts to ASCII.
Converts spaces to hyphens. Removes characters that aren’t alphanumerics, underscores, or hyphens. Converts to lowercase. Also strips leading and trailing whitespace.
{var $s = 'Our 10. product'}
{$s|webalize} {* outputs 'our-10-product' *}
Requires package nette/utils.