使用 FileStreamResult 删除临时文件

public IActionResult DownloadTempFile()
{
    string tempFilePath = Path.Combine(Path.GetTempPath(), "tempfile.txt");
    using (var stream = new FileStream(tempFilePath, FileMode.Open))
    {
        return new FileStreamResult(stream, "application/octet-stream")
        {
            FileDownloadName = "tempfile.txt"
        };
    }
}

public IActionResult DownloadTempFile()
{
    string tempFilePath = Path.Combine(Path.GetTempPath(), "tempfile.txt");
    using (var stream = new FileStream(tempFilePath, FileMode.Open))
    {
        var result = new FileStreamResult(stream, "application/octet-stream")
        {
            FileDownloadName = "tempfile.txt"
        };
        System.IO.File.Delete(tempFilePath);
        return result;
    }
}