replaceNonNumbers method
Replaces all characters that are not digits (0-9) with the replacement
string.
For example, 'abc123def'.replaceNonNumbers(replacement: '-')
results in '---123---'
.
Implementation
String replaceNonNumbers({String replacement = ''}) =>
// The regex \D matches any non-digit character and replaces it.
replaceAll(RegExp(r'\D'), replacement);