如何使用 httpclient 指定下载文件的目标

Question

I have the need to convert this PS cmdlet to C#

invoke-webrequest -uri [uri] -method GET -headers [myHeader] -outfile  [myFile]

where [uri] is the download link, [myHeader] contains my apikey and my outfile is the name of the destination file.

The invoke-webrequest in PS works but my project requires C# code. I can use the following code for the normal get or post action if I were dealing with the standard json:

        var msg = new HttpRequestMessage(HttpMethod.Get, [uri]);
        msg.Headers.Add(_apiKeyTag, _myKey);
        var resp = await _httpClient.SendAsync(msg);

Assuming _httpClient is created by new HttpClient and assuming the download link [uri] exists. The file to be downloaded is either a pdf, jpg, img or csv file. I am not sure how to convert the above comdlet in PS to C#.

How do I specify my destination file? (I am referring to the option -outfile in PS)

Answer 1

Never use anything but HttpClient . If you catch yourself typing WebClient of anything other than HttpClient , kindly slap your hand away from the keyboard.

You want to download a file with HttpClient ? Here is an example of how to do that:

private static readonly HttpClient _httpClient = new HttpClient();

private static async Task DoSomethingAsync()
{
    using (var msg = new HttpRequestMessage(HttpMethod.Get, new Uri("https://www.example.com")))
    {
        msg.Headers.Add("x-my-header", "the value");
        using (var req = await _httpClient.SendAsync(msg))
        {
            req.EnsureSuccessStatusCode();
            using (var s = await req.Content.ReadAsStreamAsync())
            using (var f = File.OpenWrite(@"c:\users\andy\desktop\out.txt"))
            {
                await s.CopyToAsync(f);
            }
        }
    }
}

You can do anything you want with HttpClient . No reason to use RestClient , WebClient , HttpWebRequest or any of those other "wannabe" Http client implementations.