WKWebView与JS交互

WKWebView与js交互有两种方式（url截取、消息回调）
方式一（截取）

//js发消息给oc（loadURL的方式）
    function test2(){
    loadURL("jiege://test2?name=js通过url给oc发消息");
    }
    function loadURL(url) {
                var iFrame;
                iFrame = document.createElement("iframe");
                iFrame.setAttribute("src", url);
                iFrame.setAttribute("style", "display:none;");
                iFrame.setAttribute("height", "0px");
                iFrame.setAttribute("width", "0px");
                iFrame.setAttribute("frameborder", "0");
                document.body.appendChild(iFrame);
                // 发起请求后这个 iFrame 就没用了，所以把它从 dom 上移除掉
                iFrame.parentNode.removeChild(iFrame);
                iFrame = null;
            }

//oc接收js消息（拦截url）

/// 是否允许加载网页 在发送请求之前，通过拦截url决定是否跳转
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler
{
NSURL * urlString = [navigationAction.request URL];
    //通过拦截urlString做交互
    if ([[urlString scheme] isEqualToString:@"test"]) {
       [_webModel jsCallObjectCTarget:self methodString:[urlString host] query:[urlString query]];
        decisionHandler(WKNavigationActionPolicyCancel);
    }
 decisionHandler(WKNavigationActionPolicyAllow);
}

方式二 （回调）
oc接收js回调接收消息，首先在oc端注册回调，然后js发送消息

//oc注册通知
    WKUserContentController *contentCon = [[WKUserContentController alloc]init];
    [contentCon addScriptMessageHandler:self name:@"test"];
    WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc]init];
    configuration.userContentController = contentCon;

    _wkWebView = [[WKWebView alloc]initWithFrame:CGRectZero configuration:configuration];
    _wkWebView.UIDelegate = self;
    _wkWebView.navigationDelegate = self;
    _wkWebView.allowsBackForwardNavigationGestures = YES;
    [self.view addSubview:_wkWebView];
    [_wkWebView mas_makeConstraints:^(MASConstraintMaker *make) {
        make.edges.equalTo(self.view);
    }];
//js发出通知
function test()      
  {
           var message = {'test' :'You choose the A'};
            window.webkit.messageHandlers.myName.postMessage(message);
 }

//oc接收通知
//添加的js方法的回调
-(void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message
{
   NSDictionary * messageDic = [[NSDictionary alloc]initWithDictionary:message.body];
    NSString *test = messageDic[@"test"];

}

oc发消息给js

//注意：js不带参数方法后面加（） 带参数加（json）
    [_wkWebView evaluateJavaScript:[NSString stringWithFormat:@"%@()",testCallBack] completionHandler:^(id _Nullable response, NSError * _Nullable error) {
        NSLog(@"%@",response);
    }];
//如果调取js的alert弹窗WKWebView需要实现以下代理：
- (void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(void))completionHandler{
    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"提示" message:message?:@"" preferredStyle:UIAlertControllerStyleAlert];
    [alertController addAction:([UIAlertAction actionWithTitle:@"确认" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        completionHandler();
    }])];
    [self presentViewController:alertController animated:YES completion:nil];
    
}
- (void)webView:(WKWebView *)webView runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(BOOL))completionHandler{
    //    DLOG(@"msg = %@ frmae = %@",message,frame);
    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"提示" message:message?:@"" preferredStyle:UIAlertControllerStyleAlert];
    [alertController addAction:([UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
        completionHandler(NO);
    }])];
    [alertController addAction:([UIAlertAction actionWithTitle:@"确认" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        completionHandler(YES);
    }])];
    [self presentViewController:alertController animated:YES completion:nil];
}
- (void)webView:(WKWebView *)webView runJavaScriptTextInputPanelWithPrompt:(NSString *)prompt defaultText:(NSString *)defaultText initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(NSString * _Nullable))completionHandler{
    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:prompt message:@"" preferredStyle:UIAlertControllerStyleAlert];
    [alertController addTextFieldWithConfigurationHandler:^(UITextField * _Nonnull textField) {
        textField.text = defaultText;
    }];
    [alertController addAction:([UIAlertAction actionWithTitle:@"完成" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        completionHandler(alertController.textFields[0].text?:@"");
    }])];
   
    [self presentViewController:alertController animated:YES completion:nil];
}