One Event for Multiple TextBoxes WPF

Question

I have multiple (> 10) TextBoxes that are used to store monetary values. As the user types, I want to format the input as a currency.

I could create one method for every TextBox but that means the creation of > 10 methods. I would rather create one method that multiple TextBoxes may use. For example:

private void OnCurrencyTextBox_PreviewTextInput(object sender, 
TextCompositionEventArgs e)
{
    CurrencyTextBox.Text = FormattedCurrency(CurrencyTextBox.Text);
}

However, this would only work for a TextBox named CurrencyTextBox . Of course there would need to be other checks for if the key is a digit etc but for the purpose of this question I am focusing on how I can apply one method to multiple TextBoxes.

Answer 1

Cast the sender argument to TextBox :

private void OnCurrencyTextBox_PreviewTextInput(object sender,
TextCompositionEventArgs e)
{
    TextBox textBox = (TextBox)sender;
    textBox.Text = FormattedCurrency(textBox.Text);
}

You can then use the same event handler for all TextBox elements:

<TextBox x:Name="t1" PreviewTextInput="OnCurrencyTextBox_PreviewTextInput" />
<TextBox x:Name="t2" PreviewTextInput="OnCurrencyTextBox_PreviewTextInput" />
...

Answer 2

使用 StringFormat=C 定义文本框。

<TextBox Text="{Binding Path=TextProperty, StringFormat=C}"/>

Answer 3

sender is Control for which event is fired:

private void OnCurrencyTextBox_PreviewTextInput(object sender, 
TextCompositionEventArgs e)
{
    ((TextBox)sender).Text = FormattedCurrency(((TextBox)sender).Text);
}