<form method="post" enctype="multipart/form-data" action="@Url.Action("Upload")">

    <input type="file" id="file" name="file"/>

    <button>提交</button>

</form>

public IActionResult Upload()

{

    var file = Request.Form.Files[];

    if (file==null||file.Length==)

    {

        return Content("文件为空");

    }

    var pathBase = Directory.GetCurrentDirectory();

    var uploadPath = Path.Combine(pathBase, "Upload");

    if (!Directory.Exists(uploadPath))

    {

        Directory.CreateDirectory(uploadPath);

    }

    string name = Guid.NewGuid().ToString() + file.FileName;

    string filePath = Path.Combine(uploadPath,name);

    using (var statem=System.IO.File.Create(filePath))

    {

        file.CopyTo(statem);

    }

    return Content("上传成功");

}