var keyboard = new Inline_Keyboard[2][];
keyboard[0] = new Inline_Keyboard[1];
keyboard[1] = new Inline_Keyboard[2];
rootobject.inline_keyboard = keyboard;
rootobject.inline_keyboard[0][0] = new Inline_Keyboard()
{
text = "Button1",
callback_data = "Button1"
};
rootobject.inline_keyboard[1][0] = new Inline_Keyboard()
{
text = "Button2",
callback_data = "Button2"
};
rootobject.inline_keyboard[1][1] = new Inline_Keyboard()
{
text = "Button3",
callback_data = "Button3"
};