How to upload file to an ASP.NET Core controller?

Question

I have this client code on web-client to load some kind of file.

fileUploaded(files) {
        files.forEach(async ifile => {
            await axios.post('http://localhost:5000/api/upload', ifile)
            .then(res => {
                console.log(res)
            }).catch(err => {
                console.error(err); 
            });
        });
}

My endpoint code looks like this:

[HttpPost("upload")]
public async Task<IActionResult> UploadFile([FromBody] IFormFile file)
{
    var data = new byte[file.Length];

    using (var bstream = file.OpenReadStream())
    {
        while (bstream.CanRead)
        {
            bstream.Read(data);
        }
    }

    // etc

    return Ok();
}

Parameter file is always null. How to deliver this file from the client the right way?

Answer 1

Instead of

UploadFile([FromBody] IFormFile file)

Use

UploadFile([FromForm] IFormFile file)

And

fileUploaded(files) {
        files.forEach(async ifile => {
            const formData = new FormData();
            formData.append('file', ifile)
            await axios.post('http://localhost:5000/api/upload', formData)
            .then(res => {
                console.log(res)
            }).catch(err => {
                console.error(err); 
            });
        });
}

Answer 2

in the UploadFile method, just, do this

//if asp.net mvc
var file1 = System.Web.HttpContext.Current.Request.Files[0];

//if asp.net core
var file2 = Request.Form.Files[0];