lettersOnly method
Extracts only ASCII letter characters (A-Z, a-z) from this string.
Note: This is ASCII-only; Unicode letters like 'é' or '你' are removed.
Example:
'Hello123World!'.lettersOnly(); // 'HelloWorld'
'abc-def'.lettersOnly(); // 'abcdef'
'123'.lettersOnly(); // ''
'café'.lettersOnly(); // 'caf' (é removed)
Implementation
@useResult
String lettersOnly() {
if (isEmpty) {
return '';
}
return replaceAll(_alphaOnlyRegex, '');
}