在Xamarin表单中删除Entry控件中的下划线

using Xamarin.Forms;

namespace YourNamespace
{
    public class CustomEntry : Entry
    {
    }
}

using Android.Content;
using YourNamespace;
using YourNamespace.Droid;
using Xamarin.Forms;
using Xamarin.Forms.Platform.Android;

[assembly: ExportRenderer(typeof(CustomEntry), typeof(CustomEntryRenderer))]
namespace YourNamespace.Droid
{
    public class CustomEntryRenderer : EntryRenderer
    {
        public CustomEntryRenderer(Context context) : base(context)
        {
        }

        protected override void OnElementChanged(ElementChangedEventArgs<Entry> e)
        {
            base.OnElementChanged(e);

            if (Control != null)
            {
                Control.Background = null; // 删除下划线
            }
        }
    }
}

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:YourNamespace"
             x:Class="YourNamespace.YourPage">
    <StackLayout>
        <local:CustomEntry Placeholder="Enter text" />
    </StackLayout>
</ContentPage>