> For the complete documentation index, see [llms.txt](https://docs.fortifiedid.se/expressions/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fortifiedid.se/expressions/extensions/str.md). # str The str extension contains string helper function for validation and comparison. ## size Returns the size/length of a string. If the supplied value isn't a string, -1 is returned. ### Syntax `str.size(value)` ### Arguments
NameTypeDescription
valuestringThe string whose length is calculated and returned. If empty, 0 is returned. If null, undefined or not a string, -1 is returned.
### Example(s) ``` // Check if value is a string and larger than 3 characters str.size(scope.value) > 3 ``` ## isString Returns `true` if the supplied value is a string, otherwise `false`. ### Syntax `str.isString(value)` ### Arguments
NameTypeDescription
valuestringThe value to check
### Example(s) ``` str.isString('this is a string') // true str.isString(99) // false (number) ``` ## isNullOrEmpty Returns `true` if the supplied value is `null`/`undefined` or an empty string (`""`). ### Syntax `str.isNullOrEmpty(value)` ### Arguments
NameTypeDescription
valuestringThe value to check
### Example(s) ``` str.isNullOrEmpty(null) // true str.isNullOrEmpty("") // true str.isNullOrEmpty('this is a string') // false ``` ## isNotNullOrEmpty Returns `true` if the supplied value is a string and is *not* `null`/`undefined` or empty (`""`). ### Syntax `str.isNotNullOrEmpty(value)` ### Arguments
NameTypeDescription
valuestringThe value to check
### Example(s) ``` str.isNotNullOrEmpty(null) // false str.isNotNullOrEmpty("") // false str.isNotNullOrEmpty('this is a string') // true ``` ## isEqual Returns `true` if the supplied values are strings with identical content, possible with different case. ### Syntax `str.isEqual(s1, s2[, ignoreCase])` ### Arguments
NameTypeDescription
s1stringThe first string to compare for equality
s2stringThe second string to compare for equality
ignoreCasebooleanFlag turning on case-insensitive compare (default: false)
### Example(s) ``` str.isEqual('string value', 'string value') // true str.isEqual('string value', 'other string value') // false str.isEqual('string value', 'STRING VALUE') // false str.isEqual('string value', 'STRING VALUE', true) // true ``` ## isEqualIgnoreCase Returns `true` if the supplied values are strings with identical content, always ignoring different case. This function is equivalent to `str.isEqual(s1, s2, true)` ### Syntax `str.isEqualIgnoreCase(s1, s2)` ### Arguments
NameTypeDescription
s1stringThe first string to compare for equality
s2stringThe second string to compare for equality
### Example(s) ``` str.isEqualIgnoreCase('string value', 'string value') // true str.isEqualIgnoreCase('string value', 'other string value') // false str.isEqualIgnoreCase('string value', 'STRING VALUE') // true ``` ## matchAny Returns `true` if the supplied value match any of the supplied regular expressions (regex). ### Syntax `str.matchAny(value, regex[,regex, ...])` ### Arguments
NameTypeDescription
valuestringThe value to match
regexstring | regexOne or more regular expressions used for matching.
### Example(s) ``` // plain string regex str.matchAny('value', 'v.*') // true // typed regex (format: /regex/flags) str.matchAny('value', /v.*/) // true str.matchAny('value', /[0-9]{1,3}/) // false // case insensitive match using i-flag str.matchAny('value', /V.*/i) // true ```