private void OnTextBoxKeyDown(object sender, KeyEventArgs e)
{
_manualChange = _manualChange || e.Key == Key.Back || e.Key == Key.Delete || e.Key == Key.Decimal || e.Key == Key.OemComma || e.Key == Key.OemPeriod;
if (NumericInputMode.HasFlag(NumericInput.Decimal) && (e.Key == Key.Decimal || e.Key == Key.OemPeriod))
{
TextBox textBox = sender as TextBox;
if (textBox.Text.Contains(this.SpecificCultureInfo.NumberFormat.NumberDecimalSeparator) == false)
{
//the control doesn't contai the decimal separator
//so we get the current caret index to insert the current culture decimal separator
var caret = textBox.CaretIndex;
//update the control text
textBox.Text = textBox.Text.Insert(caret, this.SpecificCultureInfo.NumberFormat.CurrencyDecimalSeparator);
//move the caret to the correct position
textBox.CaretIndex = caret + 1;
}
e.Handled = true;
}
}
protected void OnPreviewTextInput(object sender, TextCompositionEventArgs e)
{
e.Handled = true;
if (string.IsNullOrWhiteSpace(e.Text) || e.Text.Length != 1)
{
return;
}
TextBox textBox = (TextBox)sender;
CultureInfo equivalentCulture = SpecificCultureInfo;
NumberFormatInfo numberFormatInfo = equivalentCulture.NumberFormat;
string text = e.Text;
if (char.IsDigit(text[0]))
{
if (textBox.Text.IndexOf(numberFormatInfo.NegativeSign, textBox.SelectionStart + textBox.SelectionLength, StrComp) < 0 &&
textBox.Text.IndexOf(numberFormatInfo.PositiveSign, textBox.SelectionStart + textBox.SelectionLength, StrComp) < 0)
{
e.Handled = false;
}
}
else
{
bool allTextSelected = textBox.SelectedText == textBox.Text;
if (numberFormatInfo.NumberDecimalSeparator == text)
{
if (textBox.Text.All(i => i.ToString(equivalentCulture) != numberFormatInfo.NumberDecimalSeparator) || allTextSelected)
{
if (NumericInputMode.HasFlag(NumericInput.Decimal))
{
e.Handled = false;
}
}
}
else
{
if (numberFormatInfo.NegativeSign == text ||
text == numberFormatInfo.PositiveSign)
{
if (textBox.SelectionStart == 0)
{
// check if text already has a + or - sign
if (textBox.Text.Length > 1)
{
if (allTextSelected ||
(!textBox.Text.StartsWith(numberFormatInfo.NegativeSign, StrComp) &&
!textBox.Text.StartsWith(numberFormatInfo.PositiveSign, StrComp)))
{
e.Handled = false;
}
}
else
{
e.Handled = false;
}
}
else if (textBox.SelectionStart > 0)
{
string elementBeforeCaret = textBox.Text.ElementAt(textBox.SelectionStart - 1).ToString(equivalentCulture);
if (elementBeforeCaret.Equals(ScientificNotationChar, StrComp) && NumericInputMode.HasFlag(NumericInput.Decimal))
{
e.Handled = false;
}
}
}
else if (text.Equals(ScientificNotationChar, StrComp) &&
NumericInputMode.HasFlag(NumericInput.Decimal) &&
textBox.SelectionStart > 0 &&
!textBox.Text.Any(i => i.ToString(equivalentCulture).Equals(ScientificNotationChar, StrComp)))
{
e.Handled = false;
}
}
}
this._manualChange = this._manualChange || !e.Handled;
}