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Index

@page "/"
@using System.Collections.Generic;
@using System.Linq;

@if (Terminals == null)
{
    <p><em>Loading...</em></p>
}
else
{
    <select bind="@SelectedTerminalId">
        <option value=@(0)></option>
        @foreach (var Terminal in Terminals)
        {
            <option value="@Terminal.TerminalId">@Terminal.Name</option>
        }
    </select>
}

@if (SelectedTerminalId != default)
{
    var prices = Terminals.Single(x => x.TerminalId == SelectedTerminalId).Prices;

    <select bind="@SelectedPriceSettingId">
        <option value=@(0)></option>
        @foreach (var price in prices)
        {
            <option value="@price.Id">@price.Name (@price.Value)</option>
        }
    </select>

}

@functions {
    private static readonly List<Terminal> Terminals = new List<Terminal>{
            new Terminal{
                TerminalId = 1, Name = "NYC", Prices = new List<PriceSetting>
                {
                    new PriceSetting{Id = 1, Name = "test1", Value = 104.13m},
                    new PriceSetting{Id = 2, Name = "test2", Value = 105.13m }
                }
            },
            new Terminal{
                TerminalId = 2, Name = "LHR", Prices = new List<PriceSetting>
                {
                    new PriceSetting{Id = 3, Name = "test3", Value = 106.13m}

                }
            }
        };


    int _selectedTerminalId;
    int SelectedTerminalId
    {
        get => _selectedTerminalId;
        set
        {
            _selectedTerminalId = value;
            SelectedPriceSettingId = default;
        }
    }

    int SelectedPriceSettingId { get; set; }    
}   


namespace BlazorFiddleProject
{
    using Microsoft.AspNetCore.Blazor.Builder;
    using Microsoft.Extensions.DependencyInjection;
    using System.Collections.Generic;

    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
        }

        public void Configure(IBlazorApplicationBuilder app)
        {
            app.AddComponent<App>("app");
        }
    }

    public class PriceSetting {
        public int Id { get; set; }
        public string Name { get; set; }
        public decimal Value { get; set; }
    }

    public class Terminal {
        public int TerminalId { get; set; }
        public string Name { get; set; }
        public List<PriceSetting> Prices { get; set; }
    }
}

<!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/4.1.3/css/bootstrap.min.css"/>

    <style>
        
        
    </style>

    <script type="text/javascript">

    </script>
</head>
<body>
<app>Loading...</app>

<script src="_framework/blazor.webassembly.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.bundle.min.js"></script>
</body>
</html>

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