// 1.WKWebView的配置
        WKUserContentController *userContentController = [[WKUserContentController alloc] init];
        [userContentController addScriptMessageHandler:self name:@"myName"];
        _wkConfig = [[WKWebViewConfiguration alloc] init];
        _wkConfig.userContentController = userContentController;
        _wkwebView = [[WKWebView alloc] initWithFrame:self.view.bounds configuration:_wkConfig];

// 2.iOS 8 引入WKWebView, WKWebView 不支持JavaScriptCore的方式但提供message handler的方式为JavaScript 与Objective-C 通信.

在Objective-C 中使用WKWebView的以下方法调用JavaScript:

- (void)evaluateJavaScript:(NSString *)javaScriptString

         completionHandler:(void (^)(id, NSError *))completionHandler

如果JavaScript 代码出错, 可以在completionHandler 进行处理.

 [_wkwebView evaluateJavaScript:@"onPayComplete(1)" completionHandler:nil];// OC调用JS函数，可传参数

//3. WKScriptMessageHandler protocol?

- (void)userContentController:(WKUserContentController *)userContentController

    didReceiveScriptMessage:(WKScriptMessage *)message

{

    NSLog(@"Message: %@", message.body);

}

// 4.在JavaScript 将信息发给Objective-C:

// window.webkit.messageHandlers.<name>.postMessage();?

function postMyMessage()? {?

    var message = { ‘message‘ : ‘Hello, World!‘, ‘numbers‘ : [ 1, 2, 3 ] };?

    window.webkit.messageHandlers.myName.postMessage(message);?

}

WKWebView和JS交互