How to send multiple values from browser to unity webgl game?

I’ve seen in the docs that I can communicate from my website with the unity app by sending messages:

SendMessage('MyGameObject', 'MyFunction', 'MyValue');  

but how can I send multiple values down to the function of that object using only one SendMessage?
Maybe that function needs several values…
Or can I pass some object and parse it with C#?

Thank you

So as it does not seem to be possible to send anything else than numbers and strings. The solution I came up with for now is sending a string with JS and then parsing it inside C#:

In Javascript Browser Code:

gameInstance.SendMessage(

    'Cylinder', 'HandleRotationString', '10|0|30'

 );

In C# Unity Code:

void HandleRotationString(string coordinates) {

    string[] coord = coordinates.Split('|');

    float x = float.Parse(coord[0]);
    float y = float.Parse(coord[1]);
    float z = float.Parse(coord[2]);

    // ... use variables

}

I hope it helps someone.