How would I extract an image link from a webpage using c#?-CodePudding

I have some code already, but let's say I have a picture box in a windows forms app which updates to a random image whenever you click it.

How do I extract an image from a website (e.g. https://prnt.sc/hello1)

The image link is located under in the src=

<img  src="https://image.prntscr.com/image/HENolz07Ty_AA4RwYdZVGg.png" crossorigin="anonymous" alt="Lightshot screenshot" id="screenshot-image" image-id="hello1">

The code I have already is:

var image = "";
pictureBox1.ImageLocation = image;
pictureBox1.Update();

How could I (with only the page page url) find the image on the page and define it to 'image' (preferably using c#)

CodePudding user response：

use AngleSharp to get the page HTML and then select the desired element using various selectors. Then you can use the HttpClient to download the file

using AngleSharp;
using System.Net;

var config = Configuration.Default.WithDefaultLoader();
var address = "https://prnt.sc/hello1";
var context = BrowsingContext.New(config);
var document = await context.OpenAsync(address);
var imgSelector = "#screenshot-image";
var cells = document.QuerySelectorAll(imgSelector);
var imageAddress = cells.First().GetAttribute("src");

var client = new HttpClient();
var stream = await client.GetStreamAsync(imageAddress);

using (var fileStream = File.Create(AppDomain.CurrentDomain.BaseDirectory   @"\img.png"))
{
    stream.CopyTo(fileStream);
}