error with function using vtkArrayCalculator

Hello everyone,

I’m creating streamline with vtkstreamtracer and in order to create vector from my data I’m using vtkArrayCalculator.

So far the data array name I was using was just a single word without space and had no issue so far.
Now I would like to handle the possibility to have a data array name that contain space.

I saw that in Paraview this could be achieved by using double quote but in VTK (C#), I have the following error:
Syntax error: expecting a variable name; see position 5

position 5 is the first double quote.

below is my code.

string FeatureName = "all";
string Function = "iHat*\"" + FeatureName + "\"+jHat*\"" + FeatureName + "\"+kHat*\"" + FeatureName + "\"";
vtkArrayCalculator Calculator = new vtkArrayCalculator();
Calculator.AddScalarArrayName(FeatureName, 0);

Could you please tell my how to fix the issue?
I really thank you in advance for your help