Why does my file always show null when attempting to upload

I want to upload a file. The problem I have is the parameter is always null

My HTML

<form action="Admin/UploadImage/" method="post" enctype="multipart/form-data">
   <input type="file" id="file">
   <input type="submit">
</form>

and my controller is

[HttpPost]
[Route("UploadImage")]
public async Task<string> UploadImage([FromForm] IFormFile file) 
{
    //file is always null... 
    return "hi";
}

I have tried ([FromBody] IFormFile file) and (IFormFile file)

I load the web page and select a 50kb jpg. I then click submit (there is nothing unexpected in how I’m using this)

Why does it always show null

>Solution :

You are missing the name attribute in the <input> element.

You should add the following line :

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