Erro Video-Aula 47 Aplicação Web de Classificados

Server Error in / Application.
Input string was not in a correct format.
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.

Exception Details: System.FormatException: Input string was not in a correct format.

Source Error:

Line 49: private void populargvAnuncios()
Line 50: {
Line 51: var secaoSelecionada = int.Parse(ddlSecoes.SelectedValue);
Line 52: var anuncios = BLL.AnunciosBLL.ListarSecao(secaoSelecionada);
Line 53: gvAnuncios.DataSource = anuncios.ToList();


Source File: D:\Projetos\_Net\Classificados\Classificados.Web\Anuncios.aspx.cs Line: 51

Stack Trace:

[FormatException: Input string was not in a correct format.]
System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal) +9591163
System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info) +119
System.Int32.Parse(String s) +23
Classificados.Web.Anuncios.populargvAnuncios() in D:\Projetos\_Net\Classificados\Classificados.Web\Anuncios.aspx.cs:51
Classificados.Web.Anuncios.ddlSecoes_SelectedIndexChanged(Object sender, EventArgs e) in D:\Projetos\_Net\Classificados\Classificados.Web\Anuncios.aspx.cs:45
System.Web.UI.WebControls.ListControl.OnSelectedIndexChanged(EventArgs e) +118
System.Web.UI.WebControls.DropDownList.RaisePostDataChangedEvent() +143
System.Web.UI.WebControls.DropDownList.System.Web.UI.IPostBackDataHandler.RaisePostDataChangedEvent() +10
System.Web.UI.Page.RaiseChangedEvents() +134
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5201


Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.272