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ESelect

@page "/"
@using Microsoft.AspNetCore.Components.Forms
@using System.Linq.Expressions

@code {

    private ESelect eSelect;

    // private string eSelectResult;

    private readonly List<SelectOption> options = new List<SelectOption>
    {            
        new SelectOption { Id = 1, Value = "Jones" },
        new SelectOption { Id = 2, Value = "Smith" },
        new SelectOption { Id = 3, Value = "Bender" },
        new SelectOption { Id = 4, Value = "Baggio" },
        new SelectOption { Id = 5, Value = "Allen" },
        new SelectOption { Id = 6, Value = "Biggs" },
        new SelectOption { Id = 7, Value = "Randall" },
        new SelectOption { Id = 8, Value = "Anderson" },
        new SelectOption { Id = 8, Value = "Reeves" }
    };


    public static void ActionPlaceholder() 
    {
        Log.Print("Action - Parent Method Executed");
    }

    public void OnValueChange(ChangeEventArgs e) 
    {
        Log.Print("OnValueChange " + e.Value);
    }

    public Action EnableEnhancedSelect2 = ActionPlaceholder;

    void ValidFormSubmit() 
    {
        Log.Print("Form Submit Placeholder");
    }

    public class FormModel {
        public string LastName {get; set;}
    }    

    public FormModel Form {get; set;} = new FormModel { LastName = "Smith" };

    // for demo only to make log show on start
    protected override void OnAfterRender(bool firstRender) 
    {
        if (firstRender && Log.Items.Count > 0) StateHasChanged();
        base.OnAfterRender(firstRender);
    }
}

<EditForm Model="Form" OnValidSubmit="ValidFormSubmit" class="mt-5">
    <DataAnnotationsValidator />
    <h3>Form Example:</h3>
    <ValidationSummary />
    <h3 class="mt-4">Enhanced Select</h3>
    <ESelect Id="ESelect" @ref="eSelect" @bind-Value="Form.LastName" Options="@options" ValidationFor="@( () => Form.LastName )" 
        Label="Last Name" Trigger="EnableEnhancedSelect2"/>
    <p>Form.LastName = @Form.LastName</p>
</EditForm>

<hr/>
Log:
<ol>
    @foreach(var item in Log.Items) {
        <li>@item</li>
    }
</ol>

namespace BlazorFiddleProject
{
    using Microsoft.AspNetCore.Components.Builder;
    using Microsoft.Extensions.DependencyInjection;
    using System.Collections.Generic;

    public class SelectOption
    {
        public int Id { get; set; }
        public string Value { get; set; }
    }

    public static class Log {

        public static List<string> Items {get; set;} = new List<string>();

        public static void Print(string text) {
            Items.Insert(0, text);
        }
    }


    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
        }

        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></title>
</head>
<body>
    <app>Loading...</app>
    <script src="_framework/blazor.webassembly.js"></script>
</body>
</html>

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