数だけテキストボックス（WPF）

Question

可能性の重複：

How do I get a TextBox to only accept numeric input in WPF?

以下のコードが正しくありません：

private void txtCode_PreviewTextInput(object sender, TextCompositionEventArgs e) 
    { 
     e.Handled = !AreAllValidNumericChars(e.Text); 



    } 
    private bool AreAllValidNumericChars(string str) 
    { 
     foreach (char c in str) 
     { 
      if (!Char.IsNumber(c)) return false; 
     } 

     return true; 
    } 

と

private void txtCode_PreviewTextInput(object sender, TextCompositionEventArgs e) 
    { 
     e.Handled = !AreAllValidNumericChars(e.Text); 

    } 
    bool AreAllValidNumericChars(string str) 
    { 
     bool ret = true; 
     if (str == System.Globalization.NumberFormatInfo.CurrentInfo.CurrencyDecimalSeparator | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.CurrencyGroupSeparator | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.CurrencySymbol | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.NegativeSign | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.NegativeInfinitySymbol | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.NumberDecimalSeparator | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.NumberGroupSeparator | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.PercentDecimalSeparator | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.PercentGroupSeparator | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.PercentSymbol | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.PerMilleSymbol | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.PositiveInfinitySymbol | 
      str == System.Globalization.NumberFormatInfo.CurrentInfo.PositiveSign) 
      return ret; 

     int l = str.Length; 
     for (int i = 0; i < l; i++) 
     { 
      char ch = str[i]; 
      ret &= Char.IsDigit(ch); 
     } 

     return ret; 
    } 

と

 private override void txtCode_PreviewTextInput(object sender, TextCompositionEventArgs e) 
    { 
     char c = e.Text.ToCharArray().First(); 
     e.Handled = !(char.IsNumber(c) || char.IsControl(c)); 

    } 

と.....

問題：Ctrlキー+ Vコピー/貼り付け

正しいコードとは何ですか？

Answer 1

これは数字のテキストボックスに使用したコードであり、正常に動作しています。

private void textBox1_PreviewTextInput(object sender, TextCompositionEventArgs e) 
{ 
    e.Handled = onlyNumeric(e.Text); 
} 

public static bool onlyNumeric(string text) 
{ 
    Regex regex = new Regex("^[0-9]*$"); //regex that allows numeric input only 
    return !regex.IsMatch(text); // 
}