Difference between revisions of "Filters"

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Note: You are currently viewing documentation for Moodle 2.0. Up-to-date documentation for the latest stable version is available here: Filters.

(Replaced with content from Filters 2.0)
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{{Filters}}
 
{{Filters}}
 
<p class="note">'''Please refer to [[Page_notes#Filters|these notes]] before editing this page.'''</p>
 
<p class="note">'''Please refer to [[Page_notes#Filters|these notes]] before editing this page.'''</p>
<p class="note">'''Note:''' This page describes filters in Moodle prior to Moodle 2.0. For documentation on filters in Moodle 2.0 see [[Filters 2.0]].</p>
 
  
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Filters can transform simple text into different often more complex forms.  The potential for a filter is set at the site level and then it can be applied as needed in site on a context level.  HTML hyperlinking, or a text link that automatically calls up a sound player are examples of text filters.
  
Location: ''Administration > Modules (Plug-ins, in Moodle 2.0) > Manage filters''
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There are many applications for filters. You could turn on the LaTeX filter just for courses in the Maths and Physics categories so users could create math formula notations with text based short cuts. Here the LaTeX filter would need to be enabled for the site and you would need permission in the context of those course categories to edit the filter settings.  A teacher could turn off glossary linking in a course exam, or in the entire course.
  
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Filters are one of the general categories that can be selected for a course backup or as part of the course import process.
  
Filters allow for the automatic transformation of entered text into different, often more complex forms. For example the titles of [[Resources|resources]] can automatically become hyperlinks that take you to the relevant resource, URLs pointing to [[mp3]] files can become [[Flash]] controls embedded in the web page that let you pause and rewind the audio. The possibilities are endless and there are a number of standard filters included with Moodle and many more specialized filters available from the Moodle.org [http://moodle.org/mod/data/view.php?id=6009 Modules and plugins database].
 
  
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==Managing filters at site level==
  
==Enabling filters==
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[[Image:Manage filters 2.png|thumb|Manage filters]]
[[Image:filters admin.png|thumb|Filters administration in Moodle 1.8]]
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#In the settings block access ''Site administration > Plugins > Filters > Manage filters''
To enable a filter:
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#Select 'On', 'Off but available' or 'Disabled' as required for each filter
#Access ''Administration > Modules (Plug-ins, in 2.0) > Filters''.
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#Use the up/down arrow icons to arrange the filters in the order in which they should be applied
#On the filters administration page, click the eye icon opposite the filter you want to enable, so that it changes to an open eye.
 
#Use the up/down arrow icons to arrange the filters in the order in which they should be applied.
 
  
 
Certain filters have additional settings, which can be accessed via the links in the settings column.
 
Certain filters have additional settings, which can be accessed via the links in the settings column.
  
==Common settings==
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==Managing filters at course or activity level==
 
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[[Image:Filter settings in forum.png|thumb|Filter settings in a forum]]
Common filter settings can be found in ''Administration > Appearance > Filter settings''.
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#In the settings block access ''Course administration > Filters'' or ''Activity administration > Filters''
 
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#Set each filter on or off as required
===Text cache lifetime===
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#Click the 'Save changes' button
 
 
Text filters can take a lot of processor power to analyze. If you have a large number of courses, the filters may slow your system. The text cache lifetime determines how often the filters run. If you set them to run too frequently, your system may
 
slow down. If you set them to run too infrequently, analyzing new content will take too long and users will notice. You should experiment to find the correct amount of time for your server.
 
 
 
===Filter uploaded files===
 
 
 
This setting enables uploaded files (HTML and text only) to be processed by the filters system. You can choose to have none, only HTML or all files filtered.
 
 
 
===Filter match once per page===
 
 
 
This setting effects the glossary, activity and resource linking filters. If set to yes, only the first match on the complete page will be converted to a link. All others will be ignored.
 
 
 
===Filter match once per text===
 
 
 
This setting effects the glossary, activity and resource linking filters. If set to yes, only the first match in a discrete block of text will be converted to a link. All others in that text block will be ignored.
 
 
 
===Filter all strings===
 
 
 
If checked, headings and titles can be displayed in different languages using the [[Multi language content|multi-language filter]].
 
  
 
==Standard filters==
 
==Standard filters==
 
Filters included in the standard download are:
 
  
 
*Activity Names Auto-linking - This scans text for activity titles that exist in the same course and creates a link.
 
*Activity Names Auto-linking - This scans text for activity titles that exist in the same course and creates a link.
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*Database auto-linking - As the name suggests, this filter enables automatic linking of [[Database module]] entries.
 
*Database auto-linking - As the name suggests, this filter enables automatic linking of [[Database module]] entries.
 
:''Note'': If entries are required before viewing, the database auto-linking filter should be disabled. This is because the database auto-linking filter can't determine whether a user has submitted the required number of entries.
 
:''Note'': If entries are required before viewing, the database auto-linking filter should be disabled. This is because the database auto-linking filter can't determine whether a user has submitted the required number of entries.
*Email Protection - This filter scans the text for any email addresses. Where found they are changed (obfuscated) to reduce the chance of being added to a spammers list. However, as this filter is switched off by default, the site administrator may wish to enable this filter before importing user's email addresses.
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*Email Protection - This filter scans the text for any email addresses. Where found they are changed (obfuscated) to reduce the chance of being added to a spammers list.
 
*Glossary auto-linking - As the name suggests, this filter enables automatic linking of [[Glossary module]] entries. In addition to this filter, individual glossary entries should have the "This entry should be automatically linked" box checked.
 
*Glossary auto-linking - As the name suggests, this filter enables automatic linking of [[Glossary module]] entries. In addition to this filter, individual glossary entries should have the "This entry should be automatically linked" box checked.
*[[Multi language content]] - This filter enables resources to be created in multiple languages. It looks for &lt;span&nbsp;lang="xx" class="multilang"&gt;...&lt;/span&gt; tags which indicate that a text contains multiple languages. Then it selects and outputs the best language for the current user. The language of the resource will change when the user changes their selected Moodle language. Please note: going to the past, the multilang filter supported the &lt;lang&gt; tag. Then, officially, we changed it to the standard HTML &lt;span&gt; tag and the &lt;lang&gt; solution is now deprecated.
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*[[Multi language content]] - This filter enables resources to be created in multiple languages. It looks for &lt;span&nbsp;lang="xx" class="multilang"&gt;...&lt;/span&gt; tags which indicate that a text contains multiple languages. Then it selects and outputs the best language for the current user. The language of the resource will change when the user changes their selected Moodle language.  
 
*[[Multimedia plugins]]
 
*[[Multimedia plugins]]
 
*Resource Names Auto-linking - The titles of [[Resources]] can automatically become hyperlinks that take you to the relevant resource within the same course.
 
*Resource Names Auto-linking - The titles of [[Resources]] can automatically become hyperlinks that take you to the relevant resource within the same course.
 
*[[TeX notation filter|TeX notation]]
 
*[[TeX notation filter|TeX notation]]
*Tidy - This filter checks whether HTML code is XHTML compliant, tidying where necessary. To make this filter work you need to have PHP compiled with the libtidy option; see http://www.php.net/tidy. The Using Moodle discussion [http://moodle.org/mod/forum/discuss.php?d=28418 Tidy Filter for Moodle 1.5] contains more details.
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*HTML tidy - This filter checks whether HTML code is XHTML compliant, tidying where necessary. To make this filter work you need to have PHP compiled with the libtidy option; see http://www.php.net/tidy. The Using Moodle discussion [http://moodle.org/mod/forum/discuss.php?d=28418 Tidy Filter for Moodle 1.5] contains more details.
 
*Wiki Page Auto-linking - As the name suggests, this filter enables automatic linking between wiki pages, based on the name of the page.  It does not, however, change the behavior of linking of pages by using CamelCase or [square brackets].
 
*Wiki Page Auto-linking - As the name suggests, this filter enables automatic linking between wiki pages, based on the name of the page.  It does not, however, change the behavior of linking of pages by using CamelCase or [square brackets].
 
*[[Word censorship]] - This filter "blacks out" words found on a list.
 
*[[Word censorship]] - This filter "blacks out" words found on a list.
  
==Non-standard filters==
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There are two new filters in Moodle 2.0 onwards:
 
 
Filters are one of Moodle's pluggable resources and may be added or removed simply by using a file manager to add or remove them from the ''/filters'' directory.  Moodle detects those that are present and makes them available to use.
 
  
* [[Jmol filter|Jmol]] - for interactive 3D viewing of molecular structures
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*[[Display emoticons as images]] - This filter converts emoticons, for example :-) into smilie images.
* [[Code Syntax Highlighting]] - for more readable excerpts of programming languages including [[PHP]], [[HTML in Moodle|HTML]], [[CSS]], and XML amongst many others
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*Convert URLs into links - This filter converts URLs in selected formats, such as Moodle auto-format, to click-able links.
* [[HiddenText filter|HiddenText]] - for teachers who want to provide "hints" to students where the information is initially hidden but can easily be revealed by student in any time when he need.
 
* [[DocView filter|DocView]] - preview office documents (stored inside course's file repository) using one of the online document editing services (google docs, zoho, writely...). linked documents are opened inside a frame on the resource's page.
 
  
 
==See also==
 
==See also==
  
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*[[Common filter settings]]
 
*[[Filters FAQ]]
 
*[[Filters FAQ]]
 
*[[Filters used on the Moodle.org forums]]
 
*[[Filters used on the Moodle.org forums]]
*[[Development:Filters]]
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*[[Development:Filters 2.0]]
*Using Moodle [http://moodle.org/mod/forum/discuss.php?d=76206 Filter Demo's now online] forum discussion
 
  
 
[[Category:Filter]]
 
[[Category:Filter]]
  
[[es:Filtros (Administrador)]]
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[[fr:Filtres 2.0]]
[[fr:Filtres (administrateur)]]
 
[[ja:フィルタ]]
 

Revision as of 12:39, 6 August 2011

Please refer to these notes before editing this page.

Filters can transform simple text into different often more complex forms. The potential for a filter is set at the site level and then it can be applied as needed in site on a context level. HTML hyperlinking, or a text link that automatically calls up a sound player are examples of text filters.

There are many applications for filters. You could turn on the LaTeX filter just for courses in the Maths and Physics categories so users could create math formula notations with text based short cuts. Here the LaTeX filter would need to be enabled for the site and you would need permission in the context of those course categories to edit the filter settings. A teacher could turn off glossary linking in a course exam, or in the entire course.

Filters are one of the general categories that can be selected for a course backup or as part of the course import process.


Managing filters at site level

Manage filters
  1. In the settings block access Site administration > Plugins > Filters > Manage filters
  2. Select 'On', 'Off but available' or 'Disabled' as required for each filter
  3. Use the up/down arrow icons to arrange the filters in the order in which they should be applied

Certain filters have additional settings, which can be accessed via the links in the settings column.

Managing filters at course or activity level

Filter settings in a forum
  1. In the settings block access Course administration > Filters or Activity administration > Filters
  2. Set each filter on or off as required
  3. Click the 'Save changes' button

Standard filters

  • Activity Names Auto-linking - This scans text for activity titles that exist in the same course and creates a link.
  • Algebra - This filter will convert algebra code into GIF images. It requires the TeX filter to be installed. Note also that your system must also include the following Perl module: HTML::Entities.pm
  • Database auto-linking - As the name suggests, this filter enables automatic linking of Database module entries.
Note: If entries are required before viewing, the database auto-linking filter should be disabled. This is because the database auto-linking filter can't determine whether a user has submitted the required number of entries.
  • Email Protection - This filter scans the text for any email addresses. Where found they are changed (obfuscated) to reduce the chance of being added to a spammers list.
  • Glossary auto-linking - As the name suggests, this filter enables automatic linking of Glossary module entries. In addition to this filter, individual glossary entries should have the "This entry should be automatically linked" box checked.
  • Multi language content - This filter enables resources to be created in multiple languages. It looks for <span lang="xx" class="multilang">...</span> tags which indicate that a text contains multiple languages. Then it selects and outputs the best language for the current user. The language of the resource will change when the user changes their selected Moodle language.
  • Multimedia plugins
  • Resource Names Auto-linking - The titles of Resources can automatically become hyperlinks that take you to the relevant resource within the same course.
  • TeX notation
  • HTML tidy - This filter checks whether HTML code is XHTML compliant, tidying where necessary. To make this filter work you need to have PHP compiled with the libtidy option; see http://www.php.net/tidy. The Using Moodle discussion Tidy Filter for Moodle 1.5 contains more details.
  • Wiki Page Auto-linking - As the name suggests, this filter enables automatic linking between wiki pages, based on the name of the page. It does not, however, change the behavior of linking of pages by using CamelCase or [square brackets].
  • Word censorship - This filter "blacks out" words found on a list.

There are two new filters in Moodle 2.0 onwards:

  • Display emoticons as images - This filter converts emoticons, for example :-) into smilie images.
  • Convert URLs into links - This filter converts URLs in selected formats, such as Moodle auto-format, to click-able links.

See also