重载构造函数c#

我有一个命名空间（DXApplication5）和两个类。我正试图用一个类刷新网格视图。下面的代码我做错了什么？Thx提前，

错误：最佳重载方法与匹配"DXApplication5.grid_refresh.grid_refresh（DXApplication5.Form1）"具有一些无效的参数

参数1:无法从"DevExpress.XtraEditors.XtraForm"转换为'DXApplication5.Form1'

public class grid_refresh
{
    public DXApplication5.Form1 frm1;
    public grid_refresh()
    {
        //Default Constructor   
    }
    public grid_refresh(DXApplication5.Form1 frm1)
    {
       frm1.gcStudent.Refresh();
    }        
}

//从另一类调用

 DXApplication5.grid_refresh gr = new grid_refresh(frm1);

 public grid_refresh(DevExpress.XtraEditors.XtraForm frm1)
 {
       ...
 }