layer.open({
  title: '回车关闭测试'
  ,content: '我是内容'
  ,btn: ['确认','关闭']
  ,success: function(layero, index){
    this.enterEsc = function(event){
      if(event.keyCode === 13){
        layer.close(index);
        return false; //阻止系统默认回车事件
      }
    };
    $(document).on('keydown', this.enterEsc);	//监听键盘事件，关闭层
  }
  ,end: function(){
    $(document).off('keydown', this.enterEsc);	//解除键盘关闭事件
  }
});

function showSureDialog() {
    let index = layer.open({
        skin: "demo-class1",
        btn: ['确定','取消'],
        yes: function(index, layero){
            deleteFile(index)
        },
        title: "确认信息",
        area: ["315px", "160px"],
        content: "执行后不可恢复,确定删除此文件吗？",
    //    ++enter
        success: function(layero, index){
            $(document).on('keydown', function(e){  //document为当前元素，限制范围，如果不限制的话会一直有事件
                if(e.keyCode == 13){
                    deleteFile(index);
                }
            })
        }
    //    ++
    });
}