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@page "/"

@using System.ComponentModel.DataAnnotations

<EditForm Model="@exampleModel" OnValidSubmit="HandleValidSubmit">
    <DataAnnotationsValidator />
    <ValidationSummary />

    <InputText id="name" @bind-Value="exampleModel.Name" />

    <button type="submit">Submit</button>
</EditForm>

@code {
    public class CustomValidationAttribute : ValidationAttribute
    {
        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            var service = (IFakeService) validationContext.GetService(typeof(IFakeService));
            System.Console.WriteLine(  service.Hi );
            return ValidationResult.Success;;
        }
    }
    public class ExampleModel
    {
        [Required]
        [CustomValidationAttribute]
        [StringLength(10, ErrorMessage = "Name is too long.")]
        public string Name { get; set; }
    }
    private ExampleModel exampleModel = new ExampleModel();

    private void HandleValidSubmit()
    {
        Console.WriteLine("OnValidSubmit");
    }
}

namespace BlazorFiddleProject
{
    using Microsoft.AspNetCore.Components.Builder;
    using Microsoft.Extensions.DependencyInjection;


    public interface IFakeService { string Hi {get;}}
    public class FakeService:IFakeService
    {
        public string Hi => "hi! I'm healthy";
    }

    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddTransient<IFakeService,FakeService>();
        }

        public void Configure(IComponentsApplicationBuilder app)
        {
            app.AddComponent<App>("app");
        }
    }
}

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8"/>
    <meta name="viewport" content="width=device-width">
    <title>BlazorFiddleProject</title>
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
	
	<script src="_content/MatBlazor/dist/matBlazor.js"></script>

    <style>
        app { }
    </style>

    <script type="text/javascript">
    </script>
</head>
<body>
<app>Loading...</app>

<script src="_framework/blazor.webassembly.js"></script>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>
</body>
</html>

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