本函数检查您输入的是否为HTML格式。

bool isHTML(String str) {
          final RegExp htmlRegExp =
              RegExp('<[^>]*>', multiLine: true, caseSensitive: false);
          return htmlRegExp.hasMatch(str);
        }

示例

String input =
                "<p>Flutter is an open source framework by Google for building beautiful, natively compiled, multi-platform applications from a single codebase.</p>";
            
            bool isInHTMLFormat = Validator.isHTML(input); // output true

基于此，我们可以在Flutter_html的帮助下显示HTML内容