func webView(webView: WKWebView!, decidePolicyForNavigationAction navigationAction: WKNavigationAction!, decisionHandler: ((WKNavigationActionPolicy) -> Void)!) {
var request = NSMutableURLRequest(URL: navigationAction.request.URL)
request.setValue("value", forHTTPHeaderField: "key")
decisionHandler(.Allow)
}
在上面的代码中，我想为请求添加一个标头。我已经尝试过，navigationAction.request.setValue("IOS", forKey: "DEVICE_APP")但它不起作用。
请以任何方式帮助我。
AFAIK 可悲的是你不能用WKWebView.
它肯定不起作用，webView:decidePolicyForNavigationAction:decisionHandler:因为它navigationAction.request是只读的并且是NSURLRequest您无法更改的非可变实例。
如果我理解正确，WKWebView在单独的内容和网络进程中运行沙盒，至少在 iOS 上，没有办法拦截或更改它的网络请求。
如果您退回到UIWebView.
有很多不同的方法可以做到这一点，我发现最简单的解决方案是继承 WKWebView 并覆盖 loadRequest 方法。像这样的东西：
class CustomWebView: WKWebView {
override func load(_ request: URLRequest) -> WKNavigation? {
guard let mutableRequest: NSMutableURLRequest = request as? NSMutableURLRequest else {
return super.load(request)
}
mutableRequest.setValue("custom value", forHTTPHeaderField: "custom field")
return super.load(mutableRequest as URLRequest)
}
}
然后只需像使用 WKWebView 一样使用 CustomWebView 类。
编辑注意：这仅适用于@Stefan Arentz 指出的第一个请求。
注意：某些字段不能被覆盖，也不会被更改。我还没有进行彻底的测试，但我知道该User-Agent字段不能被覆盖，除非你做一个特定的黑客（检查这里的答案）
正如乔尼建议的那样，我已将 Au Ris 答案修改为使用NavigationAction而不是。NavigationResponse此外，这修复了随后调用相同 url 并且您不必再跟踪当前 url 的情况。这仅适用于 GET 请求，但如果需要，肯定可以适用于其他请求类型。
import UIKit
import WebKit
class ViewController: UIViewController, WKNavigationDelegate {
var webView: WKWebView?
override func viewDidLoad() {
super.viewDidLoad()
webView = WKWebView(frame: CGRect.zero)
webView!.navigationDelegate = self
view.addSubview(webView!)
// [...] set constraints and stuff
// Load first request with initial url
loadWebPage(url: "https://my.url")
}
func loadWebPage(url: URL) {
var customRequest = URLRequest(url: url)
customRequest.setValue("true", forHTTPHeaderField: "x-custom-header")
webView!.load(customRequest)
}
func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping
(WKNavigationActionPolicy) -> Void) {
if navigationAction.request.httpMethod != "GET" || navigationAction.request.value(forHTTPHeaderField: "x-custom-header") != nil {
// not a GET or already a custom request - continue
decisionHandler(.allow)
return
}
decisionHandler(.cancel)
loadWebPage(url: navigationAction.request.url!)
}
}
有一些限制，但你可以做到。拦截委托函数中的响应，如果 url 更改通过传递和重新加载 webview 来webView:decidePolicyFornavigationResponse:decisionHandler:取消它，new设置自定义标头和拦截的 url。这样，每次 url 更改（例如，用户点击链接）时，您都会取消该请求并创建一个带有自定义标题的新请求。decisionHandler(.cancel)URLRequest
import UIKit
import WebKit
class ViewController: UIViewController, WKNavigationDelegate {
var webView: WKWebView?
var loadUrl = URL(string: "https://www.google.com/")!
override func viewDidLoad() {
super.viewDidLoad()
webView = WKWebView(frame: CGRect.zero)
webView!.navigationDelegate = self
view.addSubview(webView!)
webView!.translatesAutoresizingMaskIntoConstraints = false
webView!.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 0).isActive = true
webView!.rightAnchor.constraint(equalTo: view.rightAnchor, constant: 0).isActive = true
webView!.topAnchor.constraint(equalTo: view.topAnchor, constant: 0).isActive = true
webView!.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: 0).isActive = true
// Load first request with initial url
loadWebPage(url: loadUrl)
}
func loadWebPage(url: URL) {
var customRequest = URLRequest(url: url)
customRequest.setValue("some value", forHTTPHeaderField: "custom header key")
webView!.load(customRequest)
}
// MARK: - WKNavigationDelegate
func webView(_ webView: WKWebView, decidePolicyFor navigationResponse: WKNavigationResponse, decisionHandler: @escaping (WKNavigationResponsePolicy) -> Void) {
guard let url = (navigationResponse.response as! HTTPURLResponse).url else {
decisionHandler(.cancel)
return
}
// If url changes, cancel current request which has no custom headers appended and load a new request with that url with custom headers
if url != loadUrl {
loadUrl = url
decisionHandler(.cancel)
loadWebPage(url: url)
} else {
decisionHandler(.allow)
}
}
}
以下是你的做法：策略是让你的 WKNavigationDelegate 取消请求，修改它的可变副本并重新启动它。如果已经有所需的标头，则使用 if-else 允许请求继续；否则，您将陷入无休止的加载/决定策略循环。
不确定发生了什么，但是如果您在每个请求上设置标头，就会发生奇怪的事情，因此为了获得最佳结果，只需在对您关心的域的请求上设置标头。
此处的示例为 header.domain.com 的请求设置了一个标头字段，并允许所有其他没有标头的请求：
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler {
NSURL * actionURL = navigationAction.request.URL;
if ([actionURL.host isEqualToString:@"header.domain.com"]) {
NSString * headerField = @"x-header-field";
NSString * headerValue = @"value";
if ([[navigationAction.request valueForHTTPHeaderField:headerField] isEqualToString:headerValue]) {
decisionHandler(WKNavigationActionPolicyAllow);
} else {
NSMutableURLRequest * newRequest = [navigationAction.request mutableCopy];
[newRequest setValue:headerValue forHTTPHeaderField:headerField];
decisionHandler(WKNavigationActionPolicyCancel);
[webView loadRequest:newRequest];
}
} else {
decisionHandler(WKNavigationActionPolicyAllow);
}
}
上述解决方案似乎适用于 iOS 14，但在 iOS < 14 上，POST 请求正文始终为空，导致服务器端拒绝请求。事实证明，这是 WKWebView 和 WebKit 中的一个已知错误，导致 navigationLink.Request.Body 始终为零！来自 Apple 的非常令人沮丧和愚蠢的错误，迫使 UIWebView 迁移到不稳定的 WKWebView ！
无论如何，解决方案是您应该（在取消请求之前）通过运行 javascript 函数获取 POST 正文，然后将结果分配回 navigationAction.Request（如果 navigationAction.Request.Body 为空），然后取消操作和请求再次使用更新后的 navigationAction.Request ：
解决方案在 Xamarin 中，但原生 iOS 非常接近。
[Foundation.Export("webView:decidePolicyForNavigationAction:decisionHandler:")]
public async void DecidePolicy(WebKit.WKWebView webView, WebKit.WKNavigationAction navigationAction, Action<WebKit.WKNavigationActionPolicy> decisionHandler)
{
try
{
var url = navigationAction.Request.Url;
// only apply to requests being made to your domain
if (url.Host.ToLower().Contains("XXXXX"))
{
if (navigationAction.Request.Headers.ContainsKey((NSString)"Accept-Language"))
{
var languageHeaderValue = (NSString)navigationAction.Request.Headers[(NSString)"Accept-Language"];
if (languageHeaderValue == Globalization.ActiveLocaleId)
{
decisionHandler.Invoke(WKNavigationActionPolicy.Allow);
return;
}
else
{
decisionHandler(WKNavigationActionPolicy.Cancel);
var updatedRequest = SetHeaders((NSMutableUrlRequest)navigationAction.Request);
// Temp fix for navigationAction.Request.Body always null on iOS < 14
// causing form not to submit correctly
updatedRequest = await FixNullPostBody(updatedRequest);
WebView.LoadRequest(updatedRequest);
}
}
else
{
decisionHandler(WKNavigationActionPolicy.Cancel);
var updatedRequest = SetHeaders((NSMutableUrlRequest)navigationAction.Request);
// Temp fix for navigationAction.Request.Body always null on iOS < 14
// causing form not to submit correctly
updatedRequest = await FixNullPostBody(updatedRequest);
WebView.LoadRequest(updatedRequest);
}
}
else
{
decisionHandler.Invoke(WKNavigationActionPolicy.Allow);
}
}
catch (Exception ex)
{
Logger.LogException(ex);
decisionHandler?.Invoke(WKNavigationActionPolicy.Allow);
}
}
}
private async Task<NSMutableUrlRequest> FixNullPostBody(NSMutableUrlRequest urlRequest)
{
try
{
// if on iOS 14 and higher, don't do this
//if (UIDevice.CurrentDevice.CheckSystemVersion(14, 0))
//return urlRequest;
// only resume on POST http methods
if (urlRequest.HttpMethod.ToLowerSafe() != "post")
return urlRequest;
// if post body is already there, exit
if(urlRequest.Body != null)
return urlRequest;
if (WebView == null)
return urlRequest;
// get body post by running javascript
var body = await WebView.EvaluateJavaScriptAsync("$('form').serialize()");//.ConfigureAwait(true);
if (body != null)
{
//urlRequest.Body = urlRequest.Body; // always null on iOS < 14
var bodyString = body.ToString();
if (!bodyString.IsNullOrEmpty())
urlRequest.Body = NSData.FromString(bodyString);
}
}
//This method will throw a NSErrorException if the JavaScript is not evaluated successfully.
catch (NSErrorException ex)
{
DialogHelper.ShowErrorAlert(Logger.HandleExceptionAndGetErrorMsg(ex));
}
catch (Exception ex)
{
DialogHelper.ShowErrorAlert(Logger.HandleExceptionAndGetErrorMsg(ex));
}
return urlRequest;
}
private NSMutableUrlRequest SetHeaders(NSMutableUrlRequest urlRequest)
{
try
{
if (this.UsePOST)
{
urlRequest.HttpMethod = "POST";
urlRequest.Body = postParameters.Encode(NSStringEncoding.UTF8, false);
}
var keys = new object[] { "Accept-Language" };
var objects = new object[] { Globalization.ActiveLocaleId };
var dictionnary = NSDictionary.FromObjectsAndKeys(objects, keys);
if (urlRequest.Headers == null)
{
urlRequest.Headers = dictionnary;
}
else
{
NSMutableDictionary httpHeadersCopy = new NSMutableDictionary(urlRequest.Headers);
httpHeadersCopy.Remove((NSString)"Accept-Language");
httpHeadersCopy.Add((NSString)"Accept-Language", (NSString)Globalization.ActiveLocaleId);
urlRequest.Headers = null;
urlRequest.Headers = (NSDictionary)httpHeadersCopy;
}
}
catch (Exception ex)
{
Logger.LogException(ex);
}
return urlRequest;
}
private var urlrequestCurrent: URLRequest?
func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
//print("WEB decidePolicyFor navigationAction: \(navigationAction)")
if let currentrequest = self.urlrequestCurrent {
//print("currentrequest: \(currentrequest), navigationAction.request: \(navigationAction.request)")
if currentrequest == navigationAction.request {
self.urlrequestCurrent = nil
decisionHandler(.allow)
return
}
}
decisionHandler(.cancel)
var customRequest = navigationAction.request
customRequest.setValue("myvaluefffs", forHTTPHeaderField: "mykey")
self.urlrequestCurrent = customRequest
webView.load(customRequest)
}
为了向 AJAX 请求添加自定义标头，我使用了两个三个 hack 的组合。第一个在我的原生 Swift 代码和 javascript 之间提供了一个同步通信通道。第二个覆盖 XMLHttpRequest send()方法。第三个将覆盖注入到加载到我的 WKWebView 中的网页中。
因此，组合的工作方式如下：
而不是request.setValue("value", forHTTPHeaderField: "key")：
在视图控制器中：
func webView(_ webView: WKWebView, runJavaScriptTextInputPanelWithPrompt headerName: String, defaultText _: String?, initiatedByFrame _: WKFrameInfo, completionHandler: @escaping (String?) -> Void) {
if headerName == "key" {
completionHandler("value")
} else {
completionHandler(nil)
}
}}
在 viewDidLoad 中：
let script =
"XMLHttpRequest.prototype.realSend = XMLHttpRequest.prototype.send;"
"XMLHttpRequest.prototype.send = function (body) {"
"let value = window.prompt('key');"
"this.setRequestHeader('key', value);"
"this.realSend(body)"
"};"
webView.configuration.userContentController.addUserScript(WKUserScript(source: script, injectionTime: .atDocumentEnd, forMainFrameOnly: true))
这是测试 HTML 文件：
<html>
<head>
<script>
function loadAjax() {
const xmlhttp = new XMLHttpRequest()
xmlhttp.onload = function() {
document.getElementById("load").innerHTML = this.responseText
}
xmlhttp.open("GET", "/ajax")
xmlhttp.send()
}
</script>
</head>
<body>
<button onClick="loadAjax()">Change Content</button> <br />
<pre id="load">load…</pre>
</body>
</html>
调用会/ajax带来一个通用的回声，包括所有请求标头。这样我就知道任务完成了。
我的解决方案是复制请求并添加标题然后再次加载
if navigationAction.request.value(forHTTPHeaderField: "key") == nil {
decisionHandler(.cancel)
var req:URLRequest = navigationAction.request;
req.addValue("value", forHTTPHeaderField: "key");
webView.load(req);
} else {
decisionHandler(.allow)
}