iOS WKWebView部分网页链接无法加载，求解决方案

Hey there, let's break down why this is happening and how to fix it quickly!

The Root Cause #

Unlike Safari or Chrome, which automatically infer and add the HTTP/HTTPS protocol prefix when you enter a link like www.google.com or apple.com, WKWebView is strict about URL formatting. It requires a fully qualified URL with an explicit protocol (http:// or https://) to load content properly. Without that prefix, WKWebView doesn't know how to resolve the address, hence the failed loads.

Step-by-Step Solution #

You'll need to add a quick check before loading any URL in your WKWebView to ensure the protocol is present. Here's how to implement this, even in your viewDidLoad method:

1. Create a helper function to normalize URLs

   func normalizeURL(_ urlString: String) -> URL? {
       var formattedString = urlString.trimmingCharacters(in: .whitespacesAndNewlines)
       
       // Check if the string already has a protocol
       if !formattedString.hasPrefix("http://") && !formattedString.hasPrefix("https://") {
           // Add https:// as default (you can switch to http:// if needed)
           formattedString = "https://\(formattedString)"
       }
       
       return URL(string: formattedString)
   }
   

2. Use this helper when loading URLs in WKWebView
   Modify your viewDidLoad code to leverage the helper function before initiating the web request:

   override func viewDidLoad() {
       super.viewDidLoad()
       
       let webView = WKWebView(frame: view.bounds)
       view.addSubview(webView)
       
       // Example link without prefix (replace with your target link)
       let targetLink = "www.example.com"
       if let validURL = normalizeURL(targetLink) {
           let webRequest = URLRequest(url: validURL)
           webView.load(webRequest)
       } else {
           // Handle invalid URL scenario
           print("Unable to parse the provided link into a valid URL")
       }
   }
   

Additional Notes #

• If you're handling user-input URLs, you can add extra robustness checks (like fixing cases where users type http: instead of http://) to cover edge scenarios.
• Your existing working links (with explicit http/https prefixes) will continue to work seamlessly with this helper, as it skips protocol addition when one already exists.

内容的提问来源于stack exchange，提问作者MikeIOSMike