检查此

Hi ,
Check this

cmd.Parameters.AddWithValue("@Reference", ((TextBox)Warehouse_gv.Rows[i].FindControl("textbox")).Text);
          cmd.Parameters.AddWithValue("@EditQty", ((TextBox)Warehouse_gv.Rows[i].FindControl("textbox2")).Text);

***的问候
M.Mitwalli

Best Regards
M.Mitwalli

您需要使用FindControl .

参考:
在GridView中就地编辑 [在ASP.NET 2.0中可编辑GridView [ ^ ]
带有文本框，复选框，单选按钮和下拉列表的可编辑Gridview [ ^ ]

You need to use FindControl for it.

Refer:
Inplace Edit in GridView[^]
Editable GridView in ASP.NET 2.0[^]
Editable Gridview with Textbox, CheckBox, Radio Button and DropDown List[^]