使用 C# 判斷有那些 Serial Port

    
    SerialPort ComPort = new SerialPort();
    string[] ports = SerialPort.GetPortNames();
    foreach(string portName in ports)
    {
        ComPort.PortName = portName;
        ComPort.BaudRate = 115200;
        ComPort.Parity = Parity.None;
        ComPort.StopBits = StopBits.One;
        ComPort.ReadTimeout = 500;
        ComPort.WriteTimeout = 500;
        try
        {
            ComPort.Open();
            ...
        }
        catch
        {
            ComPort.Close()
         
        }
    }

C# 呼叫 win32 API

在呼叫的函式前加入 win32API 的宣告

[DllImport("Kernel.dll")]
static extern uint QueryDosDevice(string lpDeviceName, IntPtr lpTargetPath, uint ucchMax);

public int queryFunc()
{   ...
    QueryDosDevice(...);
    ...
}

如何一次設定一個 Click Event Handler 到同一 StackPanel 裡的所有Button

ref : http://stackoverflow.com/questions/37876936/event-handler-formatting-multiple-buttons-wpf?noredirect=1&lq=1

有這樣的做法, 在前面指定 Button.Click :

<StackPanel Button.Click="button_Click" Grid.RowSpan="20">
     <Button Grid.Column="0" Grid.Row="0" FontWeight="Bold" BorderBrush="Black" Style="{StaticResource greenButton}">LT 1</Button>
     <Button x:Name="btn100" Grid.Column="0" Grid.Row="2" Style="{StaticResource greenButton}">100</Button>
     <Button x:Name="btn101" Grid.Column="0" Grid.Row="3" Style="{StaticResource greenButton}">101</Button>
     <Button x:Name="btn102" Grid.Column="0" Grid.Row="4" Style="{StaticResource greenButton}">102</Button>
 </StackPanel>

但是這樣會有 null exception 跑出來, 當然可以用 (e.OriginalSource as Button) 來避這個問題, 

也可以在 Style 裡用 EventSetter :

<Style x:Key="greenButton" TargetType="Button">
    ...
    <EventSetter Event="Click" Handler="button_Click"/>
</Style> 

WPF Binding

將 TextBox 裡的值隨著 ListBox 的選項改變

<ListBox x:Name="listBox" HorizontalAlignment="Left" Height="100" Margin="401,312,0,0" VerticalAlignment="Top" Width="100" >
    <ListBoxItem>Line 1</ListBoxItem>
    <ListBoxItem>Line 2</ListBoxItem>
</ListBox>
<TextBox x:Name="textBox" HorizontalAlignment="Left" Height="23" Margin="207,290,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="120">
    <TextBox.Text>
        <Binding ElementName="listBox" Path="SelectedItem.Content"></Binding>
    </TextBox.Text>
</TextBox>
如下圖, TextBox 裡顯示 ListBox 選的項目: