nullIf method

String? nullIf(
  1. String? comparisonString
)

Return null if this equals comparisonString. Otherwise return this.

Example

String t = 'OK'.nullIf("OK"); // returns null;
String f = 'NO'.nullIf("YES"); // returns "NO";

Implementation

String? nullIf(String? comparisonString) =>
    asIf((s) => s == comparisonString, null, this);