WKWebView与JS交互时出现Error Domain=WKErrorDomain Code=4 "A JavaScript exception occurred" UserInfo=0x170c788c0 {NSLocalizedDescription=A JavaScript exception occurred}

解决方法：

[self.WebView evaluateJavaScript:@"addtext(\"This is a text from app\");" completionHandler:^(id Result, NSError * error) {

    NSLog(@"Error -> %@", error);

}];应该放置在

 

- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation

{

}