标签:hat ESS 打开 bubuko manage toc with ica mes
我有一个功能去采集别人网站有用的内容,采集内容中有一个图片链接,可以单独打开,但放在我的网站就无法显示,出错提示:
很明显,有防盗链功能,只能在他的网站才能打开,这个好办,几行代码
在我的网站加一个中转请求,在服务端获取图片流,输出到我的客户端(localhost):
// GET: Home/PickUpImage?src=http://xxxx:yy public async Task<ActionResult> PickUpImage(string src) { if (string.IsNullOrEmpty(src)) return HttpNotFound(); var stream = await HttpHelper.GetAsync(src); return File(stream, "image/png"); }
其中 HttpHelper 是我操作HTTP请求的工具类(必须是单例模式或静态方法类,不能做成实例类) ,里面是通过 HttpClient 实现的,每次请求都会记住Cookie(重点),部分代码实现:
public class HttpHelper { private static readonly HttpClient _hc; static HttpHelper() { _hc = new HttpClient(new HttpClientHandler { AllowAutoRedirect = false, UseCookies = true }); _hc.MaxResponseContentBufferSize = 2 * 1024 * 1024; //2MB _hc.DefaultRequestHeaders.Add("user-agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36"); _hc.Timeout = new TimeSpan(0, 1, 0); //1 minute } public static async Task<Stream> GetAsync(string url) { if (url.StartsWith("https", StringComparison.OrdinalIgnoreCase)) { ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls; ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult); } return await Client.GetStreamAsync(url); } }
这样页面上img的src地址由
https://cdn.whatismyipaddress.com/images/flags/mo.png
改成
http://localhost:3721/Home/PickUpImage?src=https://cdn.whatismyipaddress.com/images/flags/mo.png
图片就能显示了
标签:hat ESS 打开 bubuko manage toc with ica mes
原文地址:https://www.cnblogs.com/felixnet/p/8972835.html