xml_get_attr: Get XML Attribute.

In curtisalexander/CRAmisc: Curtis Miscellaneous

Description

Return an XML node attribute if provided the document, XPath, and attribute name.

Usage

xml_get_attr(x, xpath, extract_value)

Arguments

x	XML document: a literal XML document, a URL, or a string
xpath	A string containing a xpath (1.0) expression.
extract_value	A string containing the attribute name to extract.

Details

Serves as a convenience function. Utilizes xml_find_first and xml_attr and will return NA_character_ if the XML attribute cannot be located or an error occurs.

Because the function uses xml_find_first, only the first match is returned.

Value

XML node attribute as a string or NA_character_ if an error occurs.

Examples

xml_doc <- "
<root_tag>
  <another_tag>
    <var_text>10</var_text>
    <var_attr value=\"10\"></var_attr>
  </another_tag>
</root_tag>
"

ten <- xml_get_attr(xml_doc,
                    "//root_tag/another_tag/var_attr",
                    "value")
identical(ten, "10")

curtisalexander/CRAmisc documentation built on May 14, 2019, 12:52 p.m.