Plugins, Hooks, & External Modules
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Plugins, Hooks, & External Modules
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Documentation for Plugins, Hooks, & External Modules
REDCap Version 14.9.1
REDCap::getFieldNames
(REDCap >= 5.5.0)
REDCap::getFieldNames
— Returns a list of all field variable names for the current project
Description
array REDCap::getFieldNames ( [ mixed $instruments = NULL ] )
Returns a list of all field variable names for the current project. If $instruments parameter is supplied (as array or string), it will only return the fields contained in the data collection instrument(s) provided in the array or string.
Parameters
instruments
An array of data collection instrument names (i.e. the unique name, not the instrument label) or a single instrument name (string), which will return only fields from that instrument. By default, NULL is used, in which it will return all field variables for the entire project.
An array of data collection instrument names (i.e. the unique name, not the instrument label) or a single instrument name (string), which will return only fields from that instrument. By default, NULL is used, in which it will return all field variables for the entire project.
Return Values
Returns array of field variable names. The variables are ordered in the order in which they are specified in the project.
Restrictions
This method can ONLY be used in a project context (i.e. when "pid" parameter is in the query string of the plugin URL) or else a fatal error is produced.
Examples
Example #1:
This example shows how one can loop through all fields in a project to perform a specific action for each one.
// Get all field variable names in project
$fields = REDCap::getFieldNames();
// Loop through each field and do something with each
foreach ($fields as $this_field) {
// Do something with $this_field
}
Example #2:
This example illustrates how to retrieve variables for only specific instruments.
// Get variables for multiple instruments in the project
$instruments = array('demographics', 'baseline_data');
var_dump( REDCap::getFieldNames($instruments) );
// Or get variables from just a single instrument
$instrument = 'demographics';
var_dump( REDCap::getFieldNames($instrument) );
REDCap 14.9.1 - © 2024 Vanderbilt University