Semi.Avalonia/demo/Semi.Avalonia.Demo/Pages/NumericUpDownDemo.axaml

<UserControl
    x:Class="Semi.Avalonia.Demo.Pages.NumericUpDownDemo"
    xmlns="https://github.com/avaloniaui"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    d:DesignHeight="800"
    d:DesignWidth="800"
    mc:Ignorable="d">
    <StackPanel HorizontalAlignment="Left" Spacing="20">
        <StackPanel.Styles>
            <Style Selector="NumericUpDown">
                <Setter Property="Width" Value="300" />
                <Setter Property="Maximum" Value="100" />
                <Setter Property="Minimum" Value="0" />
            </Style>
        </StackPanel.Styles>

        <NumericUpDown />
        <NumericUpDown Increment="10" />
        <NumericUpDown ButtonSpinnerLocation="Left" />
        <NumericUpDown ShowButtonSpinner="False" />
        <NumericUpDown Classes="Large" />
        <NumericUpDown Classes="Small" />
        <NumericUpDown InnerLeftContent="Price" InnerRightContent="$" />

        <StackPanel Orientation="Horizontal">
            <NumericUpDown
                Width="100"
                Classes="Large"
                Watermark="Large"
                ButtonSpinnerLocation="Left" />
            <NumericUpDown
                Width="100"
                Watermark="Default"
                ShowButtonSpinner="False" />
            <NumericUpDown
                Width="100"
                Watermark="Small"
                Classes="Small" />
        </StackPanel>

        <StackPanel Orientation="Horizontal">
            <NumericUpDown Width="100" ButtonSpinnerLocation="Left" />
            <NumericUpDown Width="100" ShowButtonSpinner="False" />
            <NumericUpDown Width="100" />
        </StackPanel>

        <StackPanel Orientation="Horizontal">
            <NumericUpDown Width="100" ShowButtonSpinner="False" />
            <NumericUpDown Width="100" IsEnabled="False" />
            <NumericUpDown Width="100" ButtonSpinnerLocation="Left" />
        </StackPanel>

    </StackPanel>
</UserControl>