# findFieldsByExtensionName method

FieldList findFieldsByExtensionName(

1. String? extensionName

)

Finds fields by extension name.

param extensionName A string that identifies the extension name. return The list of fields with the extension. throws BiosealException An error has occurred during Bioseal Library execution.

## Implementation

    FieldList findFieldsByExtensionName(String? extensionName) {
      Pointer<Char>? pExtensionName = extensionName?.toNativeUtf8().cast<Char>();
      FieldList resultFieldList = FieldList();
      try {
        var err = biosealSDK.id3Bioseal_FindFieldsByExtensionName(_pHandle.value, pExtensionName ?? nullptr, resultFieldList.handle);
        if (err != BiosealError.success.value) {
          resultFieldList.dispose();
          throw BiosealException(err);
        }
        return resultFieldList;
      } finally {
        if (pExtensionName != null) {
          calloc.free(pExtensionName);
        }
      }
    }