技術標籤：javajava字串

在 Java 中計算字串數值表示式可以用 javax.script.ScriptEngine#eval(java.lang.String)，通過呼叫 JavaScript 來計算

** 上程式碼 **

 public static void main(String[] args) {
        ScriptEngineManager scriptEngineManager = new ScriptEngineManager();
        ScriptEngine scriptEngine = scriptEngineManager.getEngineByName
 
("nashorn");
        String expression = "0.032*2017-58.64";

        try {
            String result = String.valueOf(scriptEngine.eval(expression));
            System.out.println(result);
        } catch (ScriptException e) {
            e.printStackTrace();
        }
    }
    // 輸出結果：5.903999999999996