public ParticleSystem.MainModule par;
    private void Start()
    {
         par = GetComponent<ParticleSystem>().main;                    
    }


public void SetColor(Color c)
    {       
        {
            par.startColor = c;
        }
    } 
//在别的类中调用SetColor会报错，但是在别的类中直接写par.startColor = c;没事

//NullReferenceException: Do not create your own module instances, get them from a ParticleSystem instance
//UnityEngine.ParticleSystem+MainModule.set_startColor (MinMaxGradient value) (at C:/buildslave/unity/build/artifacts/generated/bindings_old/common/ParticleSystem/ParticleSystemBindings.gen.cs:50)

//可我就是想调用SetColor啊，怎么办嘞