c# - 如何只接受 WPF 文本框中的整数

Question

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Answer 1

如果您不想下载 WPF 工具包(它既有 IntegerUpDown 控件也有 MaskedTextBox)，您可以根据 Masked TextBox In WPF 上的这篇文章自行实现它使用 UIElement.PreviewTextInput和 DataObject.Pasting事件。

以下是您要在窗口中放置的内容:

<Window x:Class="WpfApp1.MainWindow" Title="MainWindow" 
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <StackPanel Orientation="Vertical" Width="100" Height="100"  HorizontalAlignment="Left" VerticalAlignment="Top">

        <TextBlock Name="NumericLabel1"  Text="Enter Value:"  />
        <TextBox   Name="NumericInput1" 
                   <b>PreviewTextInput="MaskNumericInput"</b> 
                   <b>DataObject.Pasting="MaskNumericPaste"</b>  />
    </StackPanel>
</Window>

然后在代码隐藏中实现 C#:

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    <b>private void MaskNumericInput(object sender, TextCompositionEventArgs e)</b>
    {
        e.Handled = !TextIsNumeric(e.Text);
    }

    <b>private void MaskNumericPaste(object sender, DataObjectPastingEventArgs e)</b>
    {
        if (e.DataObject.GetDataPresent(typeof(string)))
        {
            string input = (string)e.DataObject.GetData(typeof(string));
            if (!TextIsNumeric(input)) e.CancelCommand();
        }
        else
        {
            e.CancelCommand();
        }
    }

    <b>private bool TextIsNumeric(string input)</b>
    {
        return input.All(c => Char.IsDigit(c) || Char.IsControl(c));
    }
}