cssExtract: Extract value from an html element

Description Usage Arguments Details Value Examples

Description

These functions have to be used in cssApply and html2df. They aim to facilitate extraction of different kind of value.

Usage

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cssLink(node)

cssClass(node)

cssId(node)

cssSrc(node)

cssValue(node)

cssName(node)

cssNumeric(node, ...)

cssCharacter(node, ...)

Arguments

node

An xml node

...

Parameters passed to xmlValue

Details

cssNumeric extracts the numeric value of an element, cssCharacter extracts text. cssLink extracts the url of a link. cssSrc, cssId, cssClass, cssName and cssValue are less usefull and extract respectively the source of an element, its id, its css class, its name and its value (may be usefull for input elements).

Value

All these function return a chracter string except cssNumeric which returns a Numeric value

Examples

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doc <- "<html>
<head></head>
<body>
  <div id='character1' class='character'>
    <span class='name'>Mike</span>
    <span class='level digit'>10</span>
    <a href='http://someurl.com'>Complete profile</a>
  </div>
  <div id='character2' class='character'>
    <span class='name'>Stan</span>
    <a href='http://someurl2.com'>Complete profile</a>
  </div>
</body>
</html>"

doc <- htmlParse(doc)

# Names of the characters
cssApply(doc, ".character>.name", cssCharacter)

# Name of character1
cssApply(doc, "#character1>.name", cssCharacter)

# Urls of the profiles
cssApply(doc, ".character>a", cssLink)

# Level of characters
cssApply(doc, ".character>.level", cssNumeric)

# character 2 does not have level, we would want to have a NA value instead of nothing
cssApplyInNodeSet(doc, ".character", ".level", cssNumeric)

cuche27/CSS documentation built on May 14, 2019, 12:49 p.m.