Download files from url to local device in .Net Core

Question

In .Net 4.0 I used WebClient to download files from an url and save them on my local drive. But I am not able to achieve the same in .Net Core.

Can anyone help me out on this?

Answer 1

WebClient is not available in .NET Core. (UPDATE: It is from 2.0) The usage of HttpClient in the System.Net.Http is therefore mandatory:

using System.Net.Http;
using System.Threading.Tasks;
...
public static async Task<byte[]> DownloadFile(string url)
{
    using (var client = new HttpClient())
    {

        using (var result = await client.GetAsync(url))
        {
            if (result.IsSuccessStatusCode)
            {
                return await result.Content.ReadAsByteArrayAsync();
            }

        }
    }
    return null;
}

Answer 2

WebClient is available from .net core 2.0

var wc = new System.Net.WebClient();
wc.DownloadFile( URL, @"c:\temp\myfile.txt");

Answer 3

In NetCore 6.0, you should use HttpClient instead of WebClient which is obsolete, and you have the async methods in the new File class.

The implementation is simple as the following:

static async Task DownloadFile(string url, string pathToSave, string fileName)
{
    var content = await GetUrlContent(url);
    if (content != null)
    {
        if (!Directory.Exists(pathToSave)) Directory.CreateDirectory(pathToSave);
        await File.WriteAllBytesAsync($"{pathToSave}/{fileName}", content);
    }
}

static async Task<byte[]?> GetUrlContent(string url)
{
    using (var client = new HttpClient())
    using (var result = await client.GetAsync(url))
        return result.IsSuccessStatusCode ? await result.Content.ReadAsByteArrayAsync():null;
}

Usage:

await DownloadFile("https://exampl.com/image.jpg", @"c:\DownloadedImages", "image.jpg");