Achieve File Upload Programmatically in ASP.NET Core Uploader control

@{
    var asyncSettings = new Syncfusion.EJ2.Inputs.UploaderAsyncSettings { SaveUrl = "https://ej2.syncfusion.com/services/api/uploadbox/Save", RemoveUrl = "https://ej2.syncfusion.com/services/api/uploadbox/Remove" };
}

<div class="col-lg-8 control-section">
    <div class="control_wrapper">
        <ejs-uploader id="UploadFiles" asyncSettings="@asyncSettings" autoUpload="false">
        </ejs-uploader>
    </div>
    <span style=' padding-left: 40px; margin-top: 30px'>
        <button id='first' class='e-btn e-control'>Upload 0th File</button>
    </span>
    <span style=' padding-left: 40px; margin-top: 30px'>
        <button id='full' class='e-btn e-control'>Upload All Files</button>
    </span>
</div>

<script>
    window.onload = function () {
        var uploadObj = document.getElementById("UploadFiles").ej2_instances[0];
        document.getElementById('first').onclick = (args) => {
            uploadObj.upload(uploadObj.getFilesData()[0]);
        };

        document.getElementById('full').onclick = (args) => {
            uploadObj.upload(uploadObj.getFilesData());
        };
    }
</script>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;

namespace EJ2CoreSampleBrowser.Controllers.TextBoxes
{
    public partial class UploaderController : Controller
    {
        public ActionResult DefaultFunctionalities()
        {
            
            return View();
        }
    }
}

.control_wrapper {
    max-width: 500px;
    margin: auto;
}

.e-upload {
    width: 100%;
    position: relative;
    margin-top: 15px;
    margin-bottom: 15px;
}

.e-upload-actions {
    display: none;
}

.e-btn {
    text-transform: none;
}

.control_wrapper .e-upload .e-upload-drag-hover {
    margin: 0;
}