How to change the size of Particle Emitter on running?

I want to change the size of Particle Emitter through the script on running.
void OnGUI()
GUI.BeginGroup(new Rect(200,0,300,300));
GUI.Label(new Rect(0, 0, 150, 30), “CloudSize”);
cloudParticleEmitter.minEmission=GUI.HorizontalSlider(new Rect(150, 30, 150, 20), cloudParticleEmitter.minEmission, 50, 80);

But it doesn’t run fine.

See this question:

The subclasses of ParticleEmitter are not exposed to scripting, so there’s not way to access the individual members of those, just those that are inherited from ParticleEmitter.

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