gf__csv__gravity_forms_create_csv.php

<?php

function populate_csv( $entry, $form ) {

	/* remove some questions from the output via label filtering */
	$exclusions = array(
		'Field Name One',
		'Field Name Two',
		'Field Name Three',
	);

	/* datetime */
	date_default_timezone_set('America/New_York');
	$date = date('U', time());

	/* user data */
	$user = get_current_user_id();

	/* file data */
	$headers = "Label\tData".PHP_EOL;
	$filename = $user.'-'.$date.'.txt';
	$field_and_response = '';	

	/* loop through the fields */
	foreach($form["fields"] as &$field) {

		/* see if this is a multi-field, like name or address */
		if (is_array($field["inputs"])) {
			
			/* loop through inputs */
			foreach($field["inputs"] as &$input) {

				/* get value from entry object; change the id to a string */
				$value = $entry[strval($input["id"])];

				/* get label; if label is not in the array of excludes */
				$label = $input["label"];
				if (!in_array($label, $exclusions)) {

					/* ...add field and response */
					$field_and_response .= $label."\t".$value.PHP_EOL;
				}
			}
		} else {
			
			/* get value from entry object; change the id to a string */
			$value = $entry[strval($field["id"])];
			
			/* get label; if label is not in the array of excludes */			
			$label = $field["label"];
			if (!in_array($label, $exclusions)) {
				
				/* ...add field and response */				
				 $field_and_response .= $label."\t".$value.PHP_EOL;
			}
		}       
	}

	/* delete existing file */
	if( file_exists($_SERVER["DOCUMENT_ROOT"].'/wp-content/uploads/folder/'.$filename) ){
		unlink( $_SERVER["DOCUMENT_ROOT"].'/wp-content/uploads/folder/'.$filename );
	}

	/* create file */
	$fh = fopen( $_SERVER["DOCUMENT_ROOT"].'/wp-content/uploads/folder/'.$filename, 'a');
	/* add headers */
	fwrite($fh, $headers);
	/* add data */
	fwrite( $fh, $field_and_response );


	/* Close the file */
	fclose($fh);

}
add_action( 'gform_after_submission', 'populate_csv', 10, 2 );

?>