选择一个组合框项XAML

Question

我试图为选项质量做一个CASE但我收到的操作员错误是“==”这个问题的解决方案是什么。？

这是

背后的代码

  private void myComboBoxThatICreatedInXaml_SelectionChanged(object sender, SelectionChangedEventArgs e)
    {

        if (myComboBoxThatICreatedInXaml.SelectedValue.ToString == Low)
        {
            QualityChoices.Add(YouTubeQuality.QualityHigh);

            case
                (myComboBoxThatICreatedInXaml.SelectedValue.ToString == Medium)
            {
                QualityChoices.Add(YouTubeQuality.QualityMedium);
            }
            case
               (myComboBoxThatICreatedInXaml.SelectedValue.ToString == High)
            {
                QualityChoices.Add(YouTubeQuality.QualityHigh);
            }

        } 

这是我的xaml代码。

   <ComboBox x:Name="myComboBoxThatICreatedInXaml" SelectionChanged="myComboBoxThatICreatedInXaml_SelectionChanged" >
            <ComboBoxItem Tag="LW">Low</ComboBoxItem>
            <ComboBoxItem Tag="MD">Medium</ComboBoxItem>
            <ComboBoxItem Tag="HG">High</ComboBoxItem>
        </ComboBox>

Answer 1

你有一些C＃语法问题。 ()方法需要ToString，字符串文字周围需要引号：

if (myComboBoxThatICreatedInXaml.SelectedValue.ToString() == "Low")

如果你想使用switch语句，那就是这样的：

switch(myComboBoxThatICreatedInXaml.SelectedValue.ToString())
{
    case "Low":
        QualityChoices.Add(YouTubeQuality.QualityHigh);
        break;
    case "Medium":
        QualityChoices.Add(YouTubeQuality.QualityMedium);
        break;
    case "High":
        QualityChoices.Add(YouTubeQuality.QualityHigh);
        break;
    default:
        break;
}