c# - 类似于自动回复的功能

Question

您好，我需要一个 WPF 应用程序的功能类似于 asp.net 中的 autopostback 选项。发生的事情是我有一个带有由 xml 文件填充的组合框的表单。因此，一旦用户选择“其他”作为选项，他们就会看到一个文本框和一个按钮。那么我的代码有什么问题吗？我使用比较字符串方法来实现该功能，但似乎它不起作用。

        private void comboBox1_SelectedIndexChanged(System.Object sender, System.EventArgs e)

    {
        if (comboBox1.SelectedValue.ToString() == "Others")
        {
            BuilderemailTextBox.Visibility = Visibility.Visible;
            BuilderupdateButton.Visibility= Visibility.Visible;
        }
        else
        {
            BuilderemailTextBox.Visibility = Visibility.Hidden;
            BuilderupdateButton.Visibility = Visibility.Hidden;
        }
    }

我还尝试了以下方法，也对 SelectedIndex 进行了更改。

        private void comboBox1_SelectedIndexChanged(System.Object sender, System.EventArgs e)

{
    if (comboBox1.SelectedIndex.ToString() == "Others")
    {
        BuilderemailTextBox.Visibility = Visibility.Visible;
        BuilderupdateButton.Visibility= Visibility.Visible;
    }
    else
    {
        BuilderemailTextBox.Visibility = Visibility.Hidden;
        BuilderupdateButton.Visibility = Visibility.Hidden;
    }
}

编辑 1:我的 XAML 文件:

<Window x:Class="WpfApplication1.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="309" Width="672">
    <Grid>
        <Button Height="23" Name="BuildButton" VerticalAlignment="Bottom" HorizontalAlignment="Left" Width="75" Click="BuildButton_Click">Build</Button>
        <ComboBox Height="23" HorizontalAlignment="Left" Margin="12,63,0,0" Name="comboBox1" VerticalAlignment="Top" Width="120" SelectionChanged="comboBox1_SelectedIndexChanged" />
        <CheckBox Height="16" HorizontalAlignment="Left" Margin="66,0,0,140" Name="ExecbuildstartingmailCheckBox" VerticalAlignment="Bottom" Width="153">Exec Build Starting Mail</CheckBox>
        <ComboBox Height="23" Margin="0,63,173,0" Name="comboBox2" VerticalAlignment="Top" HorizontalAlignment="Right" Width="120" />
        <Button Height="23" Margin="270,63,0,0" Name="BuilderupdateButton" VerticalAlignment="Top" HorizontalAlignment="Left" Width="51" Visibility="Hidden">Button</Button>
        <Button Height="23" Margin="0,63,73,0" Name="button2" VerticalAlignment="Top" HorizontalAlignment="Right" Width="74">Button</Button>
        <TextBox Height="23" HorizontalAlignment="Left" Margin="144,63,0,0" Name="BuilderemailTextBox" VerticalAlignment="Top" Width="120" Visibility="Hidden" />
    </Grid>
</Window>

edit2 我的 xml 文件:

<?xml version="1.0" encoding="utf-8"?>
<email>
  <builderemail>
    <builder>
      <value>builder@example.com</value>
    </builder>
    <builder>
      <value>Others</value>
    </builder>
  </builderemail>
  <manageremail>
    <manager>
      <value>manager@example.com</value>
    </manager>
    <manager>
      <value>Others</value>
    </manager>
  </manageremail>
</email>

Answer 1

根据您的 XML，您可以获取 SelectedItem，转换它并访问它的属性。如果您的项目有一个名为 value 的 XmlElement，您想测试它的“Other”，您可以试试这个:

(comboBox1.SelectedItem as XmlElement).GetElementsByTagName("value")[0].InnerText == "Other"