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 |
escapeUrl |
escapes parameter in URL |
noescape |
prints a variable without escaping |
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', function (string $s, int $len = 10): string {
return mb_substr($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>
generates:
<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, …
clamp (int|float min, int|float max)
Returns value clamped to the inclusive range of min and max.
{$level|clamp: 0, 255}
Also exists as function:
{=clamp($level, 0, 255)}
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}">
generates 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'}
implode (string glue = ''
)
Return a string which is the concatenation of the strings in the array. The separator between elements is an empty string per default, you can define it with the optional parameter.
{=[1, 2, 3]|implode} {* outputs '123' *}
{=[1, 2, 3]|implode:'|'} {* outputs '1|2|3' *}
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>
Generates
<div>
<p>Hello</p>
</div>
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}
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' *}
repeat (int count)
Repeats the string x-times.
{='hello'|repeat: 3} {* outputs 'hellohellohello' *}
replace (string search, string replace =
''
)
Replaces all occurrences of the search string with the replacement string.
{='hello world'|replace: 'world', 'friend'} {* outputs 'hello friend' *}
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'] *}
sort
Filter that sorts array.
{foreach ($names|sort) as $name}
...
{/foreach}
Array sorted in reverse order.
{foreach ($names|sort|reverse) as $name}
...
{/foreach}
strip
Removes unnecessary whitespace from the output.
{block |strip}
<ul>
<li>Hello</li>
</ul>
{/block}
Outputs:
<ul> <li>Hello</li> </ul>
stripHtml
Removes HTML tags and converts HTML entities to text.
{='<p>one < two</p>'|stripHtml} {* outputs 'one < two' *}
substr (int offset, int length = null)
Extracts a slice of a string. Works as the PHP function mb_substr
with fallback to iconv_substr
in
UTF‑8 mode.
{$string|substr: 1, 2}
trim
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? *}
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.
Letter Casing
Requires PHP extension mbstring
.
capitalize
Returns a title-cased version of the value. Words will start with uppercase letters, all remaining characters are lowercase.
{='i like LATTE'|capitalize} {* outputs 'I Like Latte' *}
firstUpper
Converts a first letter of value to uppercase.
{='the latte'|upper} {* outputs 'The latte' *}
lower
Converts a value to lowercase.
{='LATTE'|lower} {* outputs 'latte' *}
upper
Converts a value to uppercase.
{='latte'|upper} {* outputs 'LATTE' *}
Escaping
escapeUrl
Escapes a variable to be used as a parameter in URL.
<a href="http://example.com/{$name|escapeUrl}">{$name}</a>
noescape
Disables automatic escaping.
Security
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>
Generates:
<a data-href="">checked</a>
<a data-href="javascript:window.close()">unchecked</a>
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>
Generates:
<a href="">checked</a>
<a href="javascript:window.close()">unchecked</a>