XPath to find elements that does not have an id or class

Question

How can I get all tr elements without id attribute?

<tr id="name">...</tr>
<tr>...</tr>
<tr>...</tr>

Thanks

Answer 1

Pretty straightforward:

//tr[not(@id) and not(@class)]

That will give you all tr elements lacking both id and class attributes. If you want all tr elements lacking one of the two, use or instead of and:

//tr[not(@id) or not(@class)]

When attributes and elements are used in this way, if the attribute or element has a value it is treated as if it's true. If it is missing it is treated as if it's false.