substring-before

The substring-before function returns a string that is the part of a given string before a given substring.

Syntax

substring-before( haystack, needle )

Parameters

haystack

The string to be evaluated. Part of this string will be returned.

needle

The substring to search for. Everything before the first occurrence of needle in haystack will be returned.

Return value

A string.

Examples

XPath Example Output
substring-before('aa-bb','-') aa
substring-before('aa-bb','a') (empty string)
substring-before('aa-bb','b') aa-
substring-before('aa-bb','q') (empty string)

Specifications

XPath 1.0 4.2

Gecko support

Supported.