vue项目引入第三方js插件，单个js文件引入成功，使用该插件方法时报错

 updateTime() {
        setInterval(()=>{
          var cd = new Date();
          var lunar = calendarNU.solar2lunar();//此处是引用插件方法
          this.time = this.$options.methods.zeroPadding(cd.getHours(), 2) + ‘:‘ + this.$options.methods.zeroPadding(cd.getMinutes(), 2) + ‘:‘ + this.$options.methods.zeroPadding(cd.getSeconds(), 2);
          this.calendar = this.$options.methods.zeroPadding(cd.getFullYear(), 4) + ‘-‘ + this.$options.methods.zeroPadding(cd.getMonth()+1, 2) + ‘-‘ + this.$options.methods.zeroPadding(cd.getDate(), 2) + ‘ ‘ + this.week[cd.getDay()];
        },1000)
          
      },