Trun on/off checkboxes

For this example, when you click a submit button, the first checkbox(Mikan) will be checked and the second checkbox(Banana) will be unchecked.

CheckBoxSetValue.cshtml.cs

using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using System.ComponentModel;

namespace WorkStandard.Pages.controls
{
    public class CheckBoxSetValueModel : PageModel
    {
        [BindProperty]
        [DisplayName("Mikan")]
        public bool IsMikan { get; set; }

        [BindProperty]
        [DisplayName("Banana")]
        public bool IsBanana { get; set; } = true; //Set the initial value of the Banana to checked state.

        public void OnPost()
        {
            System.Diagnostics.Debug.WriteLineIf(IsMikan, "The Mikan is checked.");
            System.Diagnostics.Debug.WriteLineIf(IsBanana, "The Banana is checked.");

            //Make the Mikan checked and the Banana unchecked.
            ModelState.Remove(nameof(IsMikan));
            ModelState.Remove(nameof(IsBanana));

            IsMikan = true;
            IsBanana = false;
        }
    }
}

→ Where Debug.WriteLine appear

Note: Mikans are a delicious fruit of Japan. → Wikipedia

CheckBoxSetValue.cshtml

@page
@model WorkStandard.Pages.controls.CheckBoxSetValueModel

<form method="post">
    <div class="mb-3 form-check">
        <input asp-for="IsMikan" class="form-check-input" />
        <label asp-for="IsMikan" class="form-check-label"></label>
    </div>
    <div class="mb-3 form-check">
        <input asp-for="IsBanana" class="form-check-input" />
        <label asp-for="IsBanana" class="form-check-label"></label>
    </div>
    <div>
        <input type="submit" class="btn btn-primary" />
    </div>
</form>

The CSS classes...

• mb-3 Set little margin at bottom.→ Spacing
• form-check form-check-input Give the input a Bootstrap look. → Checks
• form-check form-check-label Give the label a Bootstrap look.→ Checks
• btn btn-primary Give the button a Bootstrap look to indicate that it's a key feature.→ Buttons