C# About GH_ParamAccess type

Grasshopper Developer
2

Sounds like you can perform those checks inside the component SolveInstance or BeforeSolveInstance methods just by looking at the input datatree.

private bool _validInputs;
protected override void BeforeSolveInstance()
{
  _validInputs = true;
  if (Params.Input[1].VolatileData.PathCount > 1)
  {
    AddRuntimeMessage(
      GH_RuntimeMessageLevel.Error, 
      "The second input may not contain more than a single list of items.");
    _validInputs = false;
  }
}

protected override void SolveInstance(IGH_DataAccess access)
{
  if (!_validInputs && access.Iteration > 0)
  {
    // Perhaps the Iteration check doesn't work for you, 
    // in which case the access.ParameterTargetIndex(int) or
    // access.ParameterTargetPath(int) may.
    access.DisableGapLogic();
    return;
  }
    ...
}