On this page
dataset property
Map<String, String> datasetAllows access to all custom data attributes (data-*) set on this element.
The keys for the map must follow these rules:
- The name must not begin with 'xml'.
 - The name cannot contain a semi-colon (';').
 - The name cannot contain any capital letters.
 
Any keys from markup will be converted to camel-cased keys in the map.
For example, HTML specified as:
<div data-my-random-value='value'></div>
  Would be accessed in Dart as:
var value = element.dataset['myRandomValue'];
  See also:
Source
Map<String, String> get dataset => new _DataAttributeMap(attributes); void dataset=(Source
set dataset(Map<String, String> value) {
  final data = this.dataset;
  data.clear();
  for (String key in value.keys) {
    data[key] = value[key];
  }
}
  © 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
 https://api.dartlang.org/stable/1.24.3/dart-html/Element/dataset.html