truncate method
Truncates this string to at most maxLength characters.
If the string exceeds maxLength, it is cut and suffix is appended
(defaults to "…"). The returned string's total length will be at most
maxLength (suffix length is counted).
If maxLength is less than or equal to suffix's length, only the
suffix is returned.
'Hello World'.truncate(8); // "Hello W…"
'Hello World'.truncate(12); // "Hello World" (no change)
'Hello World'.truncate(8, '...'); // "Hello..."
Implementation
String truncate(int maxLength, {String suffix = '…'}) {
if (length <= maxLength) return this;
if (maxLength <= suffix.length) return suffix;
return '${substring(0, maxLength - suffix.length)}$suffix';
}