KeyPress-Ereignis entspricht in WPF

Question

Ich habe den folgenden Code in WPA, und ich versuche, es in WPF zu konvertieren. Ich habe versucht, Keydown statt Keypress und verändern, zum Beispiel

(e.keyChar == '-') to (e.key == e.Subtract): 

1. seines nicht funktioniert die gleiche
2. Ich kann nicht das Gleichheitszeichen in e.key

ersten Code:

public partial class Form1 : Form 
{ 
    public Form1() 
    { 
     InitializeComponent(); 
     foreach (TextBox tb in this.Controls.OfType<TextBox>()) 
     { 
      tb.Enter += textBox_Enter; 
     } 
    } 

    void textBox_Enter(object sender, EventArgs e) 
    { 
     focusedTextbox = (TextBox)sender; 
    } 

private void Form1_KeyPress(object sender, KeyPressEventArgs e) 
    { 

     if (e.KeyChar == '+') 
     { 
      operand1.Real = getOperand.Real; 
      operand1.Imag = getOperand.Imag; 
      flag1 = 1; 
      e.Handled = true; 
     } 
     else if (e.KeyChar == '-') 
     { 

      if (focusedTextbox != null) 
      { 
       if (focusedTextbox.Text == "") 
       { 
        e.Handled = false; 
       } 
       else 
       { 
        e.Handled = true; 
        operand1.Real = getOperand.Real; 
        operand1.Imag = getOperand.Imag; 
        flag1 = 2; 
       } 
      } 

     } 
     else if (e.KeyChar == '*') 
     { 
      operand1.Real = getOperand.Real; 
      operand1.Imag = getOperand.Imag; 
      flag1 = 3; 
      e.Handled = true; 
     } 
     else if (e.KeyChar == '/') 
     { 
      operand1.Real = getOperand.Real; 
      operand1.Imag = getOperand.Imag; 
      flag1 = 4; 
      e.Handled = true; 
     } 
     else if (e.KeyChar == '=') 
     { 
      e.Handled = true; 
      operand2.Real = getOperand.Real; 
      operand2.Imag = getOperand.Imag; 

      switch (flag1) 
      { 
       case 1: 
        operand1 = operand1 + operand2; 
        break; 
       case 2: operand1 = operand1 - operand2; 
        break; 
       case 3: 
        operand1 = operand1 * operand2; 
        break; 
       case 4: 
        if (operand2.Magnitude == 0) 
        { 
         textBox1.Clear(); 
         textBox2.Clear(); 
         MessageBox.Show("Cannot divide by a number whose magnitude is zero"); 
         operand1 = new Complex(); 
         operand2 = new Complex(); 
         listBox1.ClearSelected(); 

        } 
        else 
        operand1 = operand1/operand2; 
        break; 
      } 
      string s = operand1.ToString(); 
      if (flag == 1) 
      { 
       string[] s1 = s.Split(' '); 

       if (s1[1] == "-") 
       { 
        textBox1.Text = s1[0]; 
        textBox2.Text = "-" + s1[3]; 
       } 
       else 
       { 
        textBox1.Text = s1[0]; 
        textBox2.Text = s1[3]; 
       } 
      } 
      else if (flag == 2) 
      { 
       string[] s1 = s.Split('@'); 
       textBox1.Text = s1[0].Trim(); 
       textBox2.Text = s1[1].Trim(); 
      } 

      listBox1.Items.Add(operand1); 
     } 

    } 

zweiter Code:

private void win_KeyDown(object sender, KeyEventArgs e) 
    { 
     if (e.Key == Key.Add) 
     { 
      operand1.Real = getOperand.Real; 
      operand1.Imag = getOperand.Imag; 
      flag1 = 1; 
      e.Handled = true; 

     } 
     else if (e.Key == Key.Subtract) 
     { 

      if (textBox2.Text == "") 
      { 
       e.Handled = false; 
      } 
      else 
      { 
       e.Handled = true; 
       operand1.Real = getOperand.Real; 
       operand1.Imag = getOperand.Imag; 
       flag1 = 2; 
      } 

     } 
     else if (e.Key == Key.Multiply) 
     { 
      operand1.Real = getOperand.Real; 
      operand1.Imag = getOperand.Imag; 
      flag1 = 3; 
      e.Handled = true; 
     } 
     else if (e.Key == Key.Divide) 
     { 
      operand1.Real = getOperand.Real; 
      operand1.Imag = getOperand.Imag; 
      flag1 = 4; 
      e.Handled = true; 
     } 
     else if (e.Key == Key.Enter) 
     { 
      e.Handled = true; 
      operand2.Real = getOperand.Real; 
      operand2.Imag = getOperand.Imag; 

      switch (flag1) 
      { 
       case 1: 
        operand1 = operand1 + operand2; 
        break; 
       case 2: operand1 = operand1 - operand2; 
        break; 
       case 3: 
        operand1 = operand1 * operand2; 
        break; 
       case 4: 
        if (operand2.Magnitude == 0) 
        { 
         textBox1.Clear(); 
         textBox2.Clear(); 
         MessageBox.Show("Cannot divide by a number whose magnitude is zero"); 
         operand1 = new Complex(); 
         operand2 = new Complex(); 
         listBox1.UnselectAll(); 
        } 
        else 
         operand1 = operand1/operand2; 
        break; 
      } 
      string s = operand1.ToString(); 
      if (flag == 1) 
      { 
       string[] s1 = s.Split(' '); 

       if (s1[1] == "-") 
       { 
        textBox1.Text = s1[0]; 
        textBox2.Text = "-" + s1[3]; 
       } 
       else 
       { 
        textBox1.Text = s1[0]; 
        textBox2.Text = s1[3]; 
       } 
      } 
      else if (flag == 2) 
      { 
       string[] s1 = s.Split('@'); 
       textBox1.Text = s1[0].Trim(); 
       textBox2.Text = s1[1].Trim(); 
      } 


      listBox1.Items.Add(operand1); 
     } 
    } 

Answer 1

Es ist sehr ähnlich - aber Sie vergleichen e.Key mit der Key-Enumeration.

Registrieren Sie Ihre Event-Handler irgendwo (wie Konstruktor oder Window_Loaded):

private void Window_Loaded(object sender, RoutedEventArgs e) 
{ 
    this.KeyDown += new KeyEventHandler(MainWindow_KeyDown); 
} 

Und dann im Ereignishandler:

void MainWindow_KeyDown(object sender, KeyEventArgs e) 
{ 
    if (e.Key == Key.Subtract) 
    { 
     // Do something 
    } 
} 

Answer 2

Sie suchen nach dem TextInput Ereignisse oder vielleicht PreviewTextInput.

Der EventArgs-Typ ist TextCompositionEventArgs; Ich glaube, dass Sie die Eigenschaft hier wollen, aber ich bin überhaupt nicht davon überzeugt.

Answer 3

<TextBox x:Name="txtbx" KeyDown="OnKeyDownHandler" Height="23" Width="250"> 
</TextBox> 

private void OnKeyDownHandler(object sender, KeyEventArgs e) 
{ 
    if (e.Key == Key.Return) 
    { 
     txtbx.Text = "You Entered: " + txtbx.Text; 
    } 
}