XPath/CSS Equivalents

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CSS Equivalents[edit]

:disabled Equivalent

//*[@disabled] represents :disabled

:checked Equivalent

//*[@checked] represents :checked

:selected Equivalent

//*[@selected] represents :selected

:text Equivalent

//*[@type="text"] represents :text

:contains Equivalent

//*[contains(text(),"you")] represents :contains("you")

:only-of-type query

//p[contains(@me,"you")] represents p[me*="you"]

Starts with Equivalent

//p[starts-with(@me,"you")] represents p[me^="you"]

Contains Equivalent

//p[starts-with(@me,concat("you",'-'))] represents p[me|="you"]

Ends with Equivalent

//p[substring(@me,string-length(@me)-2)="you"] represents p[me$="you"]

Like Equivalent

//p[contains(concat(" ",@me, " ")," you ")] represents p[me~="you"]

Negation Attribute Equivalent

//p[@me!="you"] represents p[me!="you"]

ID Equivalent

//p[@id="me"] represents p#me

:not Equivalent

//p[not(@id="me")] represents p:not(#me)

Class Equivalent

//p[contains(concat(" ", @class, " "), " me ")] represents p.me

Descendant Equivalent

//div//p represents div p

Child Equivalent

//div/p represents div > p

Adjacent Sibling Equivalent

//h1/following-sibling::div represents h1 + div

General Sibling Equivalent

//h1/following-sibling::*[count(div)] represents h1 ~ div

CSS3 / jQuery Equivalents[edit]

:nth-last-child(n) query

//*[count(child::node() ) > 0] represents hasChildNodes

:nth-last-child(n) query

/*[1] represents :root

:nth-last-child(n) query

descendant::*[1] represents :first-child

:nth-last-child(n) query

//*[last()] represents :last-child

:nth-last-child(n) query

//*[count(*)=1] represents :only-child

:nth-last-child(n) query

//*[count(*) = 0] represents :empty

:nth-last-child(n) query

//*[position() mod n = 1] represents :nth-child(n)

:nth-last-child(n) query

//*[(position() mod 2)=1] represents :nth-child(odd)

:nth-last-child(n) query

//*[(position() mod 2)=0] represents :nth-child(even)

:nth-last-child(n) query

//*[(count() - position()) mod n = 1] represents :nth-last-child(n)

:nth-of-type(n) query

//p[n] represents :nth-of-type(n)

:nth-last-of-type(n) query

//p[(count() - position()) mod n = 1] represents :nth-last-of-type(n)

:first-of-type query

descendant::p[1] represents :first-of-type

:last-of-type query

//p[last()] represents :last-of-type

:only-of-type query

//p[count(*)=1] represents :only-of-type

-moz-any/-webkit-any query

[local-name()='h1' or local-name()='h4']/node() represents -moz-any(h1,h4) *

DOM Equivalents[edit]

//mytag represents getElementsByTagName

//*[@class=$myclass] represents getElementsByClassName

//* represents childNodes

preceding-sibling::*[1] represents previousSibling

following-sibling::*[1] represents nextSibling

./following-sibling::* represents generalSibling

Conditional Logic Equivalents[edit]

-A predicate is like a SQL where clause

-A pipe is like a SQL union clause

-An axis is like a SQL t1.col = t2.col

-Use a predicate with a boolean variable check as an if statement

-Use a pipe with a tagname search as a range checker

//h2 | //h3 | //h4

-Use a pipe with a negation predicate variable check as an else statement

//var[1] | //var[not //var]

-Use a repeating axis to skip levels in the tree to retrieve nodes at every other branch

child::*/child::*

-Use variables to store individual checks within complex and/or conditional tests

-Use variables within loops to store iteration dependent variables and separate the logic from the output

-Use string-length to test the existence of functions

-Use separate tests like (a and c) or (b and c) instead of nested conditions like ((a or b) and c)

-Use string(.), local-name(.), string-length(concat(., ) ), number(.), and boolean(.)[boolean(.)] to test node values, names and existence

-Use //node()[local-name(.) = $myvar] to test for the existence of form values

-Use //node()[local-name(.) = $myvar][boolean(node())] to skip empty form values

-Always skip empty nodes when debugging

-Use local-name(.)[boolean(.)] to test for empty tags in the context node

-Use boolean(@*[not aa or not bb]) to filter known attributes

-Use {boolean((string$myvar))} to test interpolated variables

-Use boolean(following::*[1] or following::. or following::self::*) to test closing tag failures

-Use count(//*[1 | last() = 1]) to count nodes with only one child

-Use (table1 | table2)[col=val]/* to do a join

-Use *[not(@*)] to return nodes that have no attributes

-Use number(.) - number(.) to suppress number values

-Use substring(., 0, string-length(.) ) to suppress string values

-Use substring('0', 1, not($myvar) ) to set an undefined variable to zero

-Use normalize-whitespace($myvar) to remove tab characters in lists

-Use translate($myvar, $ABCvar, $abcvar) with variables storing A-Z and a-z to ignore case for node queries

-Use string-length instead of contains when checking for list position to make logic data independent

-Use use-attribute-sets to share boilerplate arguments with multiple elements, such as table or list rows

-Use * or self::* whenever selecting to return a nodeset or single node

-Use string(.) to get a node from an XML file called with the document function

-Use different delimiters between each list item to make substring-before/after logic more readable

-Use string concatenation of node/class names with counter/node values to generate ID attributes

-Use a variable to store the previous index value with a comma to make substring-after work with recursion

-Use a predicate with the boolean value of the node as a guard operator

smyvar[$myvar]

-Use XSL nodes to store local values and test XML nodes in predicates with a pipe to emulate a default operator $dynamic[$var] | $default[not($var)]

-Use the child axis instead of slash for grouping child nodes

child::(boy | girl)

-Avoid (*) because it walks the tree before testing child nodes

-Use node() instead of . when searching all elements using //

-Use a predicate check of the generate-id of the node itself and a node variable to do intersect and except set operations

-Use concat with a node and a dummy param to check for node existence

-Use string(number(.))=NaN to check existence of numeric node values

-Use not($a=$b) instead of $a !=$b when comparing variables that contain more than one node

-Use newlines after parentheses to avoid leaving one open ended

-Use predicates to check if form field names exist in the XML doc

-Use qname to get the namespace binding of a tag

-Use id() to get generate-id values instead of variable interpolation