如何在c#for windows phone应用程序中以字符串形式从列表选择器中获取selecteditem

这是我的xaml代码

<toolkit:ListPicker SelectionChanged="CountryLP_SelectionChanged" Header="--Select Mode--"  ItemsSource="{Binding CountryListdata,  ElementName=this}" x:Name="CountryLP" VerticalAlignment="Center">
    <toolkit:ListPicker.ItemTemplate>
        <DataTemplate >
            <StackPanel>
                <TextBlock  Text="{Binding country}" />
            </StackPanel>
        </DataTemplate>
    </toolkit:ListPicker.ItemTemplate>
    <toolkit:ListPicker.FullModeItemTemplate>
        <DataTemplate >
            <StackPanel>
                <TextBlock  Text="{Binding country}" />
            </StackPanel>
        </DataTemplate>
    </toolkit:ListPicker.FullModeItemTemplate>
</toolkit:ListPicker>

在页面加载过程中，控件自动转到事件CountryLP_SelectionChanged我想获得所选项目字符串

这是一个c#代码，用于将值设置为listpicker

//to get values from webservice
public class CountryList
{
    public String id{ get; set; }
    public String country{ get; set; }
}
private void CountryLP_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    if (CountryLP.SelectedItem == null)
        return;
    //var s= (sender as ListPicker).SelectedItem;
    CountryList s= CountryLP.SelectedItem as CountryList;
    //string s= CountryLP.SelectedItem as string;
    //string s= CountryLP.SelectedItem.toString();
    System.Diagnostics.Debug.WriteLine(s);
}

我尝试了几种方法，但没有得到字符串值。有人能帮我吗？

<configuration>
   <runtime>
      <legacyCorruptedStateExceptionsPolicy enabled="true" />
   </runtime>
</configuration>

var content = ((ListPickerItem)CountryLP.SelectedItem).Content;