如何用javascript禁止雙擊知道？

javascript代碼：function doubleCheck(){if (window.document.readyState != null &&window.document.readyState != 'complete'){alert("正在處理，請等待！");return false;}else{MessageClear();return true;}}在C#代碼中：this.backButton.Attributes["onClick"] = "return doubleCheck()";