WKWebview加载自签名证书https网页

验证自签名证书全过

   func webView(_ webView: WKWebView, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
        let cred = URLCredential.init(trust: challenge.protectionSpace.serverTrust!)
        completionHandler(.useCredential, cred)
    }