类型“StyleSheet”上不存在属性“insertRule”和“deleteRule”

Question

The code is used to check if a CSS Pseudo class is supported by the browser. It works fine in JavaScript but throws up errors in Typescript. Below is the typescript code:

var supportsPseudo = function(pseudoClass) {
      // Get the document stylesheet
      var ss = document.styleSheets[0];

      // Create a stylesheet if one doesn't exist
      if (!ss) {
        var el = document.createElement("style");
        document.head.appendChild(el);
        ss = document.styleSheets[0];
        document.head.removeChild(el);
      }

      // Test the pseudo-class by trying to style with it
      var testPseudo = function() {
        try {
          if (!/^:/.test(pseudoClass)) {
            pseudoClass = ":" + pseudoClass;
          }
          ss.insertRule("html" + pseudoClass + "{}", 0);
          ss.deleteRule(0);
          return true;
        } catch (e) {
          return false;
        }
      };

      // Run the test
      return testPseudo();
    };

Answer 1

尝试使用这个CSSStyleSheet接口来指定ss的类型，这里有一个链接供参考。