Difference between revisions of "API:EPrints/MetaField"

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<!-- Pod2Wiki=_preamble_  
 
<!-- Pod2Wiki=_preamble_  
 
This page has been automatically generated from the EPrints 3.2 source. Any wiki changes made between the 'Pod2Wiki=*' and 'Edit below this comment' comments will be lost.
 
This page has been automatically generated from the EPrints 3.2 source. Any wiki changes made between the 'Pod2Wiki=*' and 'Edit below this comment' comments will be lost.
  -->{{API}}{{Pod2Wiki}}{{API:Source|file=EPrints/MetaField.pm|package_name=EPrints::MetaField}}[[Category:API|MetaField]]<div><!-- Edit below this comment -->
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  -->{{API}}{{Pod2Wiki}}{{API:Source|file=perl_lib/EPrints/MetaField.pm|package_name=EPrints::MetaField}}[[Category:API|METAFIELD]][[Category:API:EPrints/MetaField|METAFIELD]]<div><!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki=_private_ --><!-- Pod2Wiki=head_name -->
 
<!-- Pod2Wiki=_private_ --><!-- Pod2Wiki=head_name -->
 
==NAME==
 
==NAME==
'''EPrints::MetaField''' - A single metadata field.
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EPrints::MetaField - A single metadata field.
 +
 
 +
<!-- Edit below this comment -->
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 +
 
 +
<!-- Pod2Wiki= -->
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<!-- Pod2Wiki=head_synopsis -->
 +
==SYNOPSIS==
 +
<source lang="perl">my $field = $dataset->field( $fieldname );
 +
$dataset = $field->dataset;
 +
$repo = $field->repository;
 +
$field->set_property( $property, $value );
 +
$value = $field->property( $property );
 +
$name = $field->name;
 +
$type = $field->type;
 +
$xhtml = $field->render_name;
 +
$xhtml = $field->render_help;
 +
$xhtml = $field->render_value_label( $value );
 +
$values = $field->all_values( %opts );
 +
$sorted_list = $field->sort_values( $unsorted_list );</source>
  
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<!-- Pod2Wiki=head_description -->
 
<!-- Pod2Wiki=head_description -->
 
==DESCRIPTION==
 
==DESCRIPTION==
Theis object represents a single metadata field, not the value of that field. A field belongs (usually) to a dataset and has a large number of properties. Optional and required properties vary between  types.
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This object represents a single metadata field, not the value of that field. A field belongs (usually) to a dataset and has a large number of properties. Optional and required properties vary between  types.
  
 
"type" is the most important property, it is the type of the metadata field. For example: "text", "name" or "date".
 
"type" is the most important property, it is the type of the metadata field. For example: "text", "name" or "date".
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A full description of metadata types and properties is in the eprints documentation and will not be duplicated here.
 
A full description of metadata types and properties is in the eprints documentation and will not be duplicated here.
  
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<!-- Pod2Wiki= -->
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<!-- Pod2Wiki=head_properties -->
<!-- Pod2Wiki=head_methods -->
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==PROPERTIES==
==METHODS==
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* replace_core =&gt; 0
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: Normally any attempt to define two fields with the same name will fail. However, you can replace a core system field by specifying the "replace_core" property. This should be used very carefully!
<span style='display:none'>User Comments</span>
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<!-- Edit below this comment -->
 
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<!-- Pod2Wiki=head_rendering -->
<!-- Pod2Wiki=item_new -->
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===Rendering===
===new===
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* render_value =&gt; CODEREF
 
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<pre> sub my_render_method
  $field = EPrints::MetaField-&gt;new( %properties )
+
  {
Create a new metafield. %properties is a hash of the properties of the  field, with the addition of "dataset", or if "dataset" is not set then "confid" and "repository" must be provided instead.
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    my( $repo, $field, $value, $all_langs, $no_link, $object ) = @_;
 +
 
 +
    return $repo->xml->create_text_node( $value );
 +
  }</pre>
  
Some field types require certain properties to be explicitly set. See the main documentation.
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: Override the default rendering of values with a custom method. Renders $value (which may be a multiple) and returns an XHTML fragment.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
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<!-- Pod2Wiki=head_read_only_properties -->
<!-- Pod2Wiki=item_final -->
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===Read-only Properties===
===final===
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* provenance =&gt; "core" or "config"
 +
: Indiciates where the field was initialised from. "core" fields are defined in {{API:PodLink|file=DataObj|package_name=DataObj|section=|text=DataObj}} classes while "config" fields are defined in cfg.d files.
  
$field-&gt;final
 
This method tells the metafield that it is now read only. Any call to set_property will produce a abort error.
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
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<!-- Pod2Wiki= -->
 
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</div>
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<!-- Pod2Wiki=head_methods -->
<!-- Pod2Wiki=item_set_property -->
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==METHODS==
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<!-- Pod2Wiki=head_set_property -->
 
===set_property===
 
===set_property===
  
$field-&gt;set_property( $property, $value )
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<source lang="perl">$field->set_property( $property, $value )
 +
 
 +
</source>
 
Set the named property to the given value.
 
Set the named property to the given value.
  
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In these cases a cloned version of the field should be used.
 
In these cases a cloned version of the field should be used.
  
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<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
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<!-- Pod2Wiki=head_repository -->
<!-- Pod2Wiki=item_clone -->
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===repository===
===clone===
 
 
 
$newfield = $field-&gt;clone
 
Clone the field, so the clone can be edited without affecting the original. Does not deep copy properties which are references - these should be set to new values, rather than the contents altered. Eg. don't push to a cloned options list, replace it.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
  
 +
<source lang="perl">$repository = $field->repository
  
<!-- Pod2Wiki= -->
+
</source>
</div>
 
<!-- Pod2Wiki=item_repository -->
 
===repository===
 
 
 
$repository = $field-&gt;repository
 
 
Return the [[API:EPrints/Repository|EPrints::Repository]] to which this field belongs.
 
Return the [[API:EPrints/Repository|EPrints::Repository]] to which this field belongs.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
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<!-- Pod2Wiki=head_dataset -->
<!-- Pod2Wiki=item_dataset -->
 
 
===dataset===
 
===dataset===
  
$dataset = $field-&gt;dataset
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<source lang="perl">$dataset = $field->dataset
 +
 
 +
</source>
 
Return the [[API:EPrints/DataSet|EPrints::DataSet]] to which this field belongs, or undef.
 
Return the [[API:EPrints/DataSet|EPrints::DataSet]] to which this field belongs, or undef.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
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<!-- Pod2Wiki=head_render_name -->
<!-- Pod2Wiki=item_render_name -->
 
 
===render_name===
 
===render_name===
  
$xhtml = $field-&gt;render_name
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<source lang="perl">$xhtml = $field->render_name
 +
 
 +
</source>
 
Render the name of this field as an XHTML object.
 
Render the name of this field as an XHTML object.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
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<!-- Pod2Wiki=head_render_help -->
<!-- Pod2Wiki=item_display_name -->
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===render_help===
===display_name===
 
 
 
$label = $field-&gt;display_name( $session )
 
DEPRECATED! Can't be removed because it's used in 2.2's default ArchiveRenderConfig.pm
 
  
Return the UTF-8 encoded name of this field, in the language of the $session.
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<source lang="perl">$xhtml = $field->render_help
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
+
</source>
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_render_help -->
 
===render_help===
 
 
 
$xhtml = $field-&gt;render_help
 
 
Return the help information for a user inputing some data for this field as an XHTML chunk.
 
Return the help information for a user inputing some data for this field as an XHTML chunk.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
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<!-- Pod2Wiki=head_name -->
<!-- Pod2Wiki=item_render_input_field -->
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===name===
===render_input_field===
 
 
 
$xhtml = $field-&gt;render_input_field( $session, $value, [$dataset], [$staff], [$hidden_fields], $obj, [$basename] )
 
Return the XHTML of the fields for an form which will allow a user to input metadata to this field. $value is the default value for this field.
 
 
 
The actual function called may be overridden from the config.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_form_value -->
 
===form_value===
 
 
 
$value = $field-&gt;form_value( $session, $object, [$prefix] )
 
Get a value for this field from the CGI parameters, assuming that the form contained the input fields for this metadata field.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
  
 +
<source lang="perl">$name = $field->name
  
<!-- Pod2Wiki= -->
+
</source>
</div>
 
<!-- Pod2Wiki=item_name -->
 
===name===
 
 
 
$name = $field-&gt;name
 
 
Return the name of this field.
 
Return the name of this field.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=head_type -->
<!-- Pod2Wiki=item_type -->
 
 
===type===
 
===type===
  
$type = $field-&gt;type
+
<source lang="perl">$type = $field->type
 +
 
 +
</source>
 
Return the type of this field.
 
Return the type of this field.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=head_property -->
<!-- Pod2Wiki=item_property -->
 
 
===property===
 
===property===
  
$value = $field-&gt;property( $property )
+
<source lang="perl">$value = $field->property( $property )
 +
 
 +
</source>
 
Return the value of the given property.
 
Return the value of the given property.
  
 
Special note about "required" property: It only indicates if the field is always required. You must query the dataset to check if it is required for a specific type.
 
Special note about "required" property: It only indicates if the field is always required. You must query the dataset to check if it is required for a specific type.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
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<!-- Pod2Wiki=head_sort_values -->
<!-- Pod2Wiki=item_is_type -->
+
===sort_values===
===is_type===
 
 
 
$boolean = $field-&gt;is_type( @typenames )
 
Return true if the type of this field is one of @typenames.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_render_value -->
 
===render_value===
 
 
 
$xhtml = $field-&gt;render_value( $session, $value, [$alllangs], [$nolink], $object )
 
Render the given value of this given string as XHTML DOM. If $alllangs  is true and this is a multilang field then render all language versions, not just the current language (for editorial checking). If $nolink is true then don't make this field a link, for example subject fields  might otherwise link to the subject view page.
 
 
 
If render_value or render_single_value properties are set then these control the rendering instead.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_render_value_no_multiple -->
 
===render_value_no_multiple===
 
 
 
$xhtml = $field-&gt;render_value_no_multiple( $session, $value, $alllangs, $nolink, $object )
 
Render the XHTML for a non-multiple value. Can be either a from a non-multiple field, or a single value from a multiple field.
 
 
 
Usually just used internally.
 
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
+
<source lang="perl">$out_list = $field->sort_values( $in_list, $langid )
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
  
 
+
</source>
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_render_value_withopts -->
 
===render_value_withopts===
 
 
 
$xhtml = $field-&gt;render_value_withopts( $session, $value, $nolink, $object )
 
Render a single value but adding the render_opts features.
 
 
 
This uses either the field specific render_single_value or, if one is configured, the render_single_value specified in the config.
 
 
 
Usually just used internally.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_sort_values -->
 
===sort_values===
 
 
 
$out_list = $field-&gt;sort_values( $session, $in_list )
 
 
Sorts the in_list into order, based on the "order values" of the  values in the in_list. Assumes that the values are not a list of multiple values. [ [], [], [] ], but rather a list of single values.
 
Sorts the in_list into order, based on the "order values" of the  values in the in_list. Assumes that the values are not a list of multiple values. [ [], [], [] ], but rather a list of single values.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=head_all_values -->
<!-- Pod2Wiki=item_list_values -->
+
===all_values===
===list_values===
 
 
 
@values = $field-&gt;list_values( $value )
 
Return a list of every distinct value in this field.
 
 
 
- for simple fields: return ( $value )
 
- for multiple fields: return @{$value}
 
 
 
This function is used by the item_matches method in Search.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_most_local -->
 
===most_local===
 
 
 
$value = $field-&gt;most_local( $session, $value )
 
If this field is a multilang field then return the version of the  value most useful for the language of the session. In order of preference: The language of the session, the default language for the repository, any language at all. If it is not a multilang field then just return $value.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_call_property -->
 
===call_property===
 
 
 
$value2 = $field-&gt;call_property( $property, @args )
 
Call the method described by $property. Pass it the arguments and return the result.
 
 
 
The property may contain either a code reference, or the scalar name of a method.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_value_from_sql_row -->
 
===value_from_sql_row===
 
 
 
$val = $field-&gt;value_from_sql_row( $session, $row )
 
Shift and return the value of this field from the database input $row.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_sql_row_from_value -->
 
===sql_row_from_value===
 
 
 
@row = $field-&gt;sql_row_from_value( $session, $value )
 
Return a list of values to insert into the database based on $value.
 
 
 
The values will normally be passed to {{API:PodLink|file=DBI|package_name=DBI|section=bind_param|text=DBI/bind_param}}:
 
 
 
  $sth-&gt;bind_param( $idx, $row[0] )
 
 
 
If the value is an array ref it gets expanded:
 
 
 
  $sth-&gt;bind_param( $idx, @{$row[0]} )
 
 
 
This is necessary to support binding LOB data under various databases.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_get_sql_properties -->
 
===get_sql_properties===
 
 
 
%opts = $field-&gt;get_sql_properties( $session )
 
Map the relevant SQL properties for this field to options passed to [[API:EPrints/Database|EPrints::Database]]::get_column_type().
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_get_sql_type -->
 
===get_sql_type===
 
 
 
@types = $field-&gt;get_sql_type( $session )
 
Return the SQL column types of this field, used for creating tables.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_create_ordervalues_field -->
 
===create_ordervalues_field===
 
 
 
$field = $field-&gt;create_ordervalues_field( $session [, $langid ] )
 
Return a new field object that this field can use to store order values, optionally for language $langid.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_get_sql_index -->
 
===get_sql_index===
 
 
 
$sql = $field-&gt;get_sql_index
 
Return the columns that an index should be created over.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_render_single_value -->
 
===render_single_value===
 
 
 
$xhtml_dom = $field-&gt;render_single_value( $session, $value )
 
Returns the XHTML representation of the value. The value will be non-multiple. Just the  simple value.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_render_input_field_actual -->
 
===render_input_field_actual===
 
 
 
$xhtml = $field-&gt;render_input_field_actual( $session, $value, [$dataset], [$staff], [$hidden_fields], [$obj], [$basename] )
 
Return the XHTML of the fields for an form which will allow a user to input metadata to this field. $value is the default value for this field.
 
 
 
Unlike render_input_field, this function does not use the render_input property, even if it's set.
 
 
 
The $obj is the current state of the object this field is associated  with, if any.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_get_sql_names -->
 
===get_sql_names===
 
 
 
@sqlnames = $field-&gt;get_sql_names
 
Return the names of this field's columns as they appear in a SQL table.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_is_browsable -->
 
===is_browsable===
 
 
 
$boolean = $field-&gt;is_browsable
 
Return true if this field can be "browsed". ie. Used as a view.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
  
 +
<source lang="perl">$values = $field->all_values( %opts )
  
<!-- Pod2Wiki= -->
+
</source>
</div>
 
<!-- Pod2Wiki=item_all_values -->
 
===all_values===
 
 
 
$values = $field-&gt;all_values( %opts )
 
 
Return a reference to an array of all the values of this field.  For fields like "subject" or "set" it returns all the variations. For fields like "text" return all  the distinct values from the database.
 
Return a reference to an array of all the values of this field.  For fields like "subject" or "set" it returns all the variations. For fields like "text" return all  the distinct values from the database.
  
 
Results are sorted according to the ordervalues of the current session.
 
Results are sorted according to the ordervalues of the current session.
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
 
<!-- Pod2Wiki=item_get_id_from_value -->
 
===get_id_from_value===
 
 
$id = $field-&gt;get_id_from_value( $session, $value )
 
Returns a unique id for $value or "NULL" if $value is undefined.
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=head_copyright -->
<!-- Pod2Wiki=item_get_value_from_id -->
+
==COPYRIGHT==
===get_value_from_id===
+
Copyright 2000-2011 University of Southampton.
 
 
$value = $field-&gt;get_value_from_id( $session, $id )
 
Returns the value from $id or undef if $id is "NULL".
 
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
+
This file is part of EPrints http://www.eprints.org/.
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
  
 +
EPrints is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
  
<!-- Pod2Wiki= -->
+
EPrints is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
</div>
 
<!-- Pod2Wiki=item_render_value_label -->
 
===render_value_label===
 
  
$xhtml = $field-&gt;render_value_label( $value )
+
You should have received a copy of the GNU Lesser General Public License along with EPrints. If not, see http://www.gnu.org/licenses/.
Return an XHTML DOM object describing the given value. Normally this is just the value, but in the case of something like a "set" field  this returns the name of the option in the current language.
 
  
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
  
  
 
<!-- Pod2Wiki= -->
 
<!-- Pod2Wiki= -->
</div>
+
<!-- Pod2Wiki=_postamble_ -->
<!-- Pod2Wiki=item_ordervalue -->
 
===ordervalue===
 
 
 
$ov = $field-&gt;ordervalue( $value, $session, $langid, $dataset )
 
Return a string representing this value which can be used to sort it into order by comparing it alphabetically.
 
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
 
<!-- Edit below this comment -->
 
<!-- Edit below this comment -->
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_xml_to_epdata -->
 
===xml_to_epdata===
 
 
$epdata = $field-&gt;xml_to_epdata( $session, $xml, %opts )
 
Populates $epdata based on $xml.
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_get_default_value -->
 
===get_default_value===
 
 
$value = $field-&gt;get_default_value( $session )
 
Return the default value for this field. This is only applicable to very simple cases such as timestamps, auto-incremented values etc.
 
 
Any complex initialisation should be done in the "set_eprint_automatic_fields" callback (or the equivalent for the given object).
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_get_index_codes -->
 
===get_index_codes===
 
 
( $terms, $grep_terms, $ignored ) = $field-&gt;get_index_codes( $session, $value )
 
Get indexable terms from $value. $terms is a reference to an array of strings to index. $grep_terms is a reference to an array of terms to add to the grep index. $ignored is a reference to an array of terms that should be ignored (e.g. stop words in a free-text field).
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_split_search_value -->
 
===split_search_value===
 
 
@terms = $field-&gt;split_search_value( $session, $value )
 
Split $value into terms that can be used to search against this field.
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_get_search_conditions -->
 
===get_search_conditions===
 
 
$cond = $field-&gt;get_search_conditions( $session, $dataset, $value, $match, $merge, $mode )
 
Return a {{API:PodLink|file=Search/Condition|package_name=Search::Condition|section=|text=Search::Condition}} for $value based on this field.
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=item_get_search_conditions_not_ex -->
 
===get_search_conditions_not_ex===
 
 
$cond = $field-&gt;get_search_conditions_not_ex( $session, $dataset, $value, $match, $merge, $mode )
 
Return the search condition for a search which is not-exact ($match ne "EX").
 
 
<div style='background-color: #e8e8f; margin: 0.5em 0em 1em 0em; border: solid 1px #cce;  padding: 0em 1em 0em 1em; font-size: 80%; '>
 
<span style='display:none'>User Comments</span>
 
<!-- Edit below this comment -->
 
 
 
<!-- Pod2Wiki= -->
 
</div>
 
<!-- Pod2Wiki=_postamble_ --><!-- Edit below this comment -->
 

Latest revision as of 09:44, 11 May 2012

EPrints 3 Reference: Directory Structure - Metadata Fields - Repository Configuration - XML Config Files - XML Export Format - EPrints data structure - Core API - Data Objects


API: Core API

Latest Source Code (3.4, 3.3) | Revision Log | Before editing this page please read Pod2Wiki


NAME

EPrints::MetaField - A single metadata field.


SYNOPSIS

my $field = $dataset->field( $fieldname );
$dataset = $field->dataset;
$repo = $field->repository;
$field->set_property( $property, $value );
$value = $field->property( $property );
$name = $field->name;
$type = $field->type;
$xhtml = $field->render_name;
$xhtml = $field->render_help;
$xhtml = $field->render_value_label( $value );
$values = $field->all_values( %opts );
$sorted_list = $field->sort_values( $unsorted_list );


DESCRIPTION

This object represents a single metadata field, not the value of that field. A field belongs (usually) to a dataset and has a large number of properties. Optional and required properties vary between types.

"type" is the most important property, it is the type of the metadata field. For example: "text", "name" or "date".

A full description of metadata types and properties is in the eprints documentation and will not be duplicated here.


PROPERTIES

  • replace_core => 0
Normally any attempt to define two fields with the same name will fail. However, you can replace a core system field by specifying the "replace_core" property. This should be used very carefully!


Rendering

  • render_value => CODEREF
  sub my_render_method
  {
    my( $repo, $field, $value, $all_langs, $no_link, $object ) = @_;
  
    return $repo->xml->create_text_node( $value );
  }
Override the default rendering of values with a custom method. Renders $value (which may be a multiple) and returns an XHTML fragment.


Read-only Properties

  • provenance => "core" or "config"
Indiciates where the field was initialised from. "core" fields are defined in DataObj classes while "config" fields are defined in cfg.d files.


METHODS

set_property

$field->set_property( $property, $value )

Set the named property to the given value.

This should not be called on metafields unless they've been cloned first.

This method will cause an abort error if the metafield is read only.

In these cases a cloned version of the field should be used.


repository

$repository = $field->repository

Return the EPrints::Repository to which this field belongs.


dataset

$dataset = $field->dataset

Return the EPrints::DataSet to which this field belongs, or undef.


render_name

$xhtml = $field->render_name

Render the name of this field as an XHTML object.


render_help

$xhtml = $field->render_help

Return the help information for a user inputing some data for this field as an XHTML chunk.


name

$name = $field->name

Return the name of this field.


type

$type = $field->type

Return the type of this field.


property

$value = $field->property( $property )

Return the value of the given property.

Special note about "required" property: It only indicates if the field is always required. You must query the dataset to check if it is required for a specific type.


sort_values

$out_list = $field->sort_values( $in_list, $langid )

Sorts the in_list into order, based on the "order values" of the values in the in_list. Assumes that the values are not a list of multiple values. [ [], [], [] ], but rather a list of single values.


all_values

$values = $field->all_values( %opts )

Return a reference to an array of all the values of this field. For fields like "subject" or "set" it returns all the variations. For fields like "text" return all the distinct values from the database.

Results are sorted according to the ordervalues of the current session.



COPYRIGHT

Copyright 2000-2011 University of Southampton.

This file is part of EPrints http://www.eprints.org/.

EPrints is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

EPrints is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with EPrints. If not, see http://www.gnu.org/licenses/.