Validate the selected value in a WPF combobox

Question

Like the title says, I am trying to validate my form, but I have an issue getting the combobox value:

<ComboBox Name="ComboBox_Country" 
          Validation.Error="Validation_Error"
          Text="{Binding UpdateSourceTrigger=PropertyChanged, 
                         Path=Form_Country,
                         ValidatesOnDataErrors=true,
                         NotifyOnValidationError=true}"/>

Which is then validated with my class FormValidation like so:

            public string this[string columnName]
            {
               get
            {
               string result = null;

               if (columnName == "Form_Country")
               {
                  if (string.IsNullOrEmpty(Form_Country) || !verifyNumericValue(Form_Country))
                    result = "Please choose a correct option.";
               }

            }

I use these functions to call the validation in my form.

    private void Confirm_CanExecute(object sender, CanExecuteRoutedEventArgs e)
    {
        e.CanExecute = _errors == 0;
        e.Handled = true;
    }

    private void Confirm_Executed(object sender, ExecutedRoutedEventArgs e)
    {
        _generic = new UnidadValidation();
        grid_UnidadData.DataContext = _generic;
        e.Handled = true;
    }

    private void Validation_Error(object sender, ValidationErrorEventArgs e)
    {
        if (e.Action == ValidationErrorEventAction.Added)
            _errors++;
        else
            _errors--;
    }

I wish to get the selected value, not the selected text. What is my best option?

Answer 1

Stupid, stupid stupid lack of observation on my part. If you were to change the ComboBox's Text to SelectedValue instead like so:

<ComboBox Name="ComboBox_Pais" 
          Validation.Error="Validation_Error"
          SelectedValue="{Binding UpdateSourceTrigger=PropertyChanged, 
                                  Path=Escuela_Pais,
                                  ValidatesOnDataErrors=true, 
                                  NotifyOnValidationError=true}"/>

One will get the selected value and NOT the text.

For those of you who might want to read on it, I found the original tutorial here.

WPF TextBox Validation with IDataErrorInfo