predicates/string_predicates library

Functions

contains(String str, String seed) → bool
Returns true if str contains seed.
containsIgnoreCase(String str, String seed) → bool
Returns true if str contains seed, ignoring case.
equals(String? str, String comparison) → bool
Returns true if str equals comparison.
isAlpha(String str) → bool
Returns true if str contains only ASCII alphabetic characters (a–z, A–Z).
isAlphaNumeric(String str) → bool
Returns true if str contains only ASCII alphanumeric characters (a–z, A–Z, 0–9).
isAscii(String str) → bool
Returns true if str contains only printable ASCII characters (U+0000–U+007F).
isBase64(String str) → bool
Returns true if str is a valid Base64-encoded string.
isByteLength(String str, int min, [int? max]) → bool
Returns true if str byte-length is within `min`, `max`.
isEmail(String str) → bool
Returns true if str matches the RFC 5322 email format heuristic.
isFloat(String str) → bool
Returns true if str represents a floating-point number.
isFullWidth(String str) → bool
Returns true if str contains full-width Unicode characters.
isHalfWidth(String str) → bool
Returns true if str contains half-width Unicode characters.
isHexadecimal(String str) → bool
Returns true if str is a valid hexadecimal string.
isHexColor(String str) → bool
Returns true if str is a valid hex color (e.g. #FFF or #FFFFFF).
isInt(String str) → bool
Returns true if str represents an integer.
isJson(String str) → bool
Returns true if str is valid JSON.
isLength(String str, int min, [int? max]) → bool
Returns true if the display-length of str is within `min`, `max`, counting surrogate pairs as single characters.
isLowerCase(String str) → bool
Returns true if str is entirely lowercase (or has no cased characters).
isMultiByte(String str) → bool
Returns true if str contains multi-byte (non-ASCII) characters.
isNull(String? str) → bool
Returns true if str is null or empty.
isNullOrEmpty(String? str) → bool
Returns true if str is null or empty.
isNumeric(String str) → bool
Returns true if str contains only numeric digits (optionally negative).
isSurrogatePair(String str) → bool
Returns true if str contains surrogate pairs.
isUpperCase(String str) → bool
Returns true if str is entirely uppercase (or has no cased characters).
isVariableWidth(String str) → bool
Returns true if str contains both full-width and half-width characters.
matches(String str, String pattern) → bool
Returns true if str matches the regex pattern.