ASP.NET

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IDataReader dr = DB.GetRS("select * from Country " + DB.GetNoLock() + " where Published = 1 order by DisplayOrder,Name");<br />
BillingCountry.DataSource = dr;<br />
BillingCountry.DataTextField = "Name";<br />
BillingCountry.DataValueField = "Name";<br />
BillingCountry.DataBind();<br />
dr.Close();<br />
BillingCountry.SelectedIndex = 0;<br />

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<asp:DropDownList ID="BillingCountry" runat="server" OnSelectedIndexChanged="BillingCountry_OnChange" AutoPostBack="True"></asp:DropDownList><br />

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static public IDataReader GetRS(String Sql)<br />
{<br />
    SqlConnection dbconn = new SqlConnection();<br />
    dbconn.ConnectionString = DB.GetDBConn();<br />
    dbconn.Open();<br />
    SqlCommand cmd = new SqlCommand(Sql, dbconn);<br />
    return cmd.ExecuteReader(CommandBehavior.CloseConnection);<br />
}<br />

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'BillingCountry' has a SelectedValue which is invalid because it does not exist in the list of items.<br />
Parameter name: value <br />
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. <br />
<br />
Exception Details: System.ArgumentOutOfRangeException: 'BillingCountry' has a SelectedValue which is invalid because it does not exist in the list of items.<br />
Parameter name: value<br />
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Source Error: <br />
Line 442:                BillingCountry.DataTextField = "Name";<br />
Line 443:                BillingCountry.DataValueField = "Name";<br />
Line 444:                BillingCountry.DataBind();<br />
Line 445:                dr.Close();<br />
Line 446:                BillingCountry.SelectedIndex = 0;<br />