add sanitization function

Author: Andrew-Paystack

includes/classes/class-settings.php

@@ -101,7 +101,7 @@ public function register_settings_fields() {
 		// Run through each group, and the fields in there.
 		foreach ( $fields as $group => $fields ) {
 			foreach ( $fields as $field_key => $args ) {
-				register_setting( 'kkd-pff-paystack-settings-group', $field_key );
+				register_setting( 'kkd-pff-paystack-settings-group', $field_key, [ $this, 'sanitise_field' ] );
 			}
 		}
 	}
@@ -191,4 +191,15 @@ public function is_option_selected( $value, $compare ) {
 		}
 		return $result;
 	}
+
+	/**
+	 * Checks to see if the curren value is selected.
+	 *
+	 * @param string $value
+	 * /
+	 * 
+	 */
+	private function sanitise_field( $value ) {
+		return sanitize_text_field( $value );
+	}
 }