How do I get at the values in the element?

I'm just a bit confused as to how I get the values entered in the `stripe-card` element. I don't want to use the block form because I have a submit button outside of this element that will send along some other data to a server endpoint that creates a paysource in the customers stripe account. Can I have the values bound to some sort of controller / component property so I can get at those later when the user hits the submit button I have outside of the element?

该 issue 没有指定任何文件、测试或入口点。首先跟踪 `stripe-card` 元素如何公开值，以及其块形式如何提交这些值；确定是否支持外部提交流程，并在行为定义后记录或测试预期的集成方式。

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