Editing Multilang field

{{fieldtypes}}


== Description ==
Allows multiple text values to be recorded representing the same text in different languages.  This is a sub-class of the [[Compound field]] as at least two sub-fields are required.  At least one to store the text and one to store the language (sub-field called <tt>lang</tt>) in which it is written.  By default a Multilang field still sets <tt>multiple => 0</tt> so if more than only one language will be used for any one record then <tt>multiple => 1</tt> also needs to be set.

The languages available for the <tt>lang</tt> sub-field are specified in the <tt>cfg/namedsets/languages</tt> file.

== Inheritance ==
* [[Metadata]]
** [[Compound field]]
*** [[Multilang field]]

== Additional Properties ==
Same as [[Compound field#Additional_Properties|Compound fields]] except for

{| border="1" cellpadding="3" cellspacing="0"
! Name !! Default Value !! Required !! Description !! Notes
|-
| '''input_boxes''' || <tt>1</tt> || NO || Number of boxes for this field in input form to insert separate values.  || Different from [[Metadata]] default (<tt>0</tt>).
|-
| '''input_ordered''' || <tt>0</tt> || NO || Whether the rows of values are numbered and therefore can be re-ordered. || Different from [[Metadata]] default (<tt>1</tt>). Ordering is unnecessary, as priority is determined based on the language sub-field value (and the repository's configuration for language prioritisation).
|-
| '''match''' || <tt>IN</tt> || NO || How to match values in search results.  || Different from [[Metadata]] default (<tt>EQ</tt>). Treat the search value as a list of whitespace-separated words rather than a single string.
|}

== Required Phrases ==
Same as [[Compound field#Required_Phrases|Compounds fields]] but rather than needing:
 datasetid + "_fieldname_" + fieldname
Multilang fields require the following phrases.  The first directly replaces the original fieldname phrase and the second specifies the language used:
 datasetid + "_fieldname_" + fieldname + "_" + subfieldname
 datasetid + "_fieldname_" + fieldname + "_lang"
As Multilang fields are compound there may be more than two phrases to add depending on the number of subfields specified.

If you were to change the <tt>title</tt> phrase for an eprint to have type <tt>multilang</tt>, you would need the phrases:
 eprint_fieldname_title_text
 eprint_fieldname_title_lang

If you modify the <tt>cfg/namedsets/languages</tt> file you will need to make sure you add the appropriate additional phrases in the form:
 languages_typename_LANGID
E.g. <tt>languages_typename_fr_ca</tt> could be <tt>French Canadian</tt>

== Database ==
Multilang fields do not have a standard way of being stored in the database as they are compound fields.  The <tt>lang</tt> sub-field will appear in the dataset table (or separate table if a <tt>multiple</tt> field) as:
 
 fieldname_lang VARCHAR(16)

== API ==
See [[API:EPrints/MetaField/Multilang|API page]].

== Examples ==
Most basic example.
 {
     name => 'title_multilang',
     type => 'multilang',
     fields => [
         {
             sub_name => 'text',
             type => 'text',
         },
     ],
 }
Multiple languages for a single record field.
 {
     name => 'title_multilang',
     type => 'multilang',
     multiple => 1,
     fields => [
         {
             sub_name => 'text',
             type => 'text',
         },
     ],
 }
More than one non-language sub-field.
 {
     name => 'question',
     type => 'multilang',
     multiple => 1,
     fields => [
         {
             sub_name => 'question',
             type => 'longtext',
         },
         {
             sub_name => 'answer',
             type => 'text',
         },
     ],
 }