public void MultiElementsTest()
{
Html html = new Html();
string headerId = "id1";
string headerName = "name1";
string headerText = "text";
string headerStyle = "color:red";
Header1 h1 = new Header1(headerText, headerId, headerName, headerStyle);
html.AddElement(h1);
Assert.Equal($"<html><h1 id=\"{headerId}\" name=\"{headerName}\" style=\"{headerStyle}\">{headerText}</h1></html>", html.ToHtml());
}