1、原因说明

• 由于安全机制,WKWebView默认对JavaScript下alert(),confirm(),prompt()）做了拦截，如果要想正常使用，需要实现WKWebView的三个代理方法.

2、解决办法

• 2.1 解决alert方法

- (void)webView:(WKWebView *)webView 
runJavaScriptAlertPanelWithMessage:(NSString *)message 
initiatedByFrame:(WKFrameInfo *)frame 
completionHandler:(void (^)(void))completionHandler {

    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:nil message:message?:@"" preferredStyle:UIAlertControllerStyleAlert];

    [alertController addAction:([UIAlertAction actionWithTitle:@"确认" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {

        completionHandler();

    }])];

    [self presentViewController:alertController animated:YES completion:nil];

}

• 2.2 解决confirm

- (void)webView:(WKWebView *)webView 
runJavaScriptConfirmPanelWithMessage:(NSString *)message  
initiatedByFrame:(WKFrameInfo *)frame 
completionHandler:(void (^)(BOOL))completionHandler {

    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];

}

• 2.3 解决prompt

- (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];
}

iOS开发 WKWebView下js的alert(),confirm(),prompt()方法无法正常执行

原文：https://www.cnblogs.com/CH520/p/11968408.html