/// <summary>
/// 将指定查询变为Excel导出，将不考虑分页，所以查出的数据量太大可能出问题 v0.2.0+
/// </summary>
/// <returns></returns>
public async Task <FileResult> Export()
{
var key = (string)this.ControllerContext.RouteData.Values["key"];
Log.ObjectId = key;
var dict = Request.Query.ToDictionary(kv => kv.Key, kv => (object)kv.Value.FirstOrDefault());
string fileName = (string)dict["filename"] ?? "导出.xlsx";
var result = await _dg.GetExcelStreamAsync(key, dict);
return(File(result, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", fileName));
}