html_element() in rvest: matching element by font size-CodePudding

MWE:

html <- minimal_html('
    <p id="name1"><font size=5>Here is size 5 font </font></p>
    <p id="name2" ><font size=3>And here is size 3 font </font></p>
   ')

html %>% html_elements('#name1')
html %>% html_elements('.second') 
html %>% html_elements('font')
html %>% html_elements('#5')
html %>% html_elements('.5')

My goal is to extract all elements with attribute "size=5". I know the easy way to do this when the attribute is "id" or "class" (as shown above) but I can't find any way to do it for the attribute "size". (I tried with both html_elements and html_nodes.) Is there a way to do this in the rvest package?

CodePudding user response：

Not sure how to do this with the CSS selectors if that's required, but here's some XPath that does the trick:

html %>% html_elements(xpath = '//font[@size=5]')

Output:

{xml_nodeset (1)}
[1] <font size="5">Here is size 5 font </font>

Or, for truly all elements with a size attribute of 5 (not just fonts):

html %>% html_elements(xpath = '//*[@size=5]')

CodePudding user response：

The css selector lists for font size 5 and for size 5

html_elements('font[size="5"]')

In the above font is the type (tag) selector and [size="5"] is the attribute = value selector.

And

html_elements('[size="5"]')

In the above, the absence of the type selector in the selector list means matching will now be on the size attribute and its associated value only.