hi
i want to use entity but i cant find a way to do that so i used entity command
i need to get field name from user with (dropdownlist1) and value with (tbnumber.txt) then update that field from my db plus new value
my code is this
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1-Dim userin_name As String = "username"
2-Dim codein As String = ""
3-db.sellitem(userin_name, DropDownList1.SelectedValue, tbfee.Text, tbnumber.Text, selected.Item(0).x_y)
4-Dim defvalu = db.ExecuteStoreCommand("select " & DropDownList1.SelectedValue & " from Equipment where user_name='username'")
5-defvalu -= tbnumber.Text
6-db.ExecuteStoreCommand("update Equipment set " & DropDownList1.SelectedValue & "=" & defvalu + tbnumber.Text & " where user_name='" & userin_name & "'")
==========
but in line 4 i allways get -1
thank you
if some ono have better idea please tell me