btnTest_Click(null, null);

前提是该方法没有使用这些参数中的任何一个(通常不使用.)

Provided that the method isn't using either of these parameters (it's very common not to.)

说实话，虽然这很恶心.如果您有需要调用的代码，则应遵循以下约定:

To be honest though this is icky. If you have code that needs to be called you should follow the following convention:

protected void btnTest_Click(object sender, EventArgs e)
{
   SomeSub();
}

protected void SomeOtherFunctionThatNeedsToCallTheCode()
{
   SomeSub();
}

protected void SomeSub()
{
   // ...
}