WKWebView 禁用 长按弹出UIMenuController

iOS8开始使用WKWebView，但实际使用过程中和UIWebView有许多区别。比如禁止在webview中长按弹出UIMenuController的操作：

---

• UIWebView中

 - (BOOL)canPerformAction:(SEL)action withSender:(id)sender
{
    return NO;
}

---

• WKWebView中，则需要通过js进行操作

// 禁止选择CSS
NSString *css = @"body{-webkit-user-select:none;-webkit-user-drag:none;}";

// CSS选中样式取消
NSMutableString *javascript = [NSMutableString string];
[javascript appendString:@"var style = document.createElement('style');"];
[javascript appendString:@"style.type = 'text/css';"];
[javascript appendFormat:@"var cssContent = document.createTextNode('%@');", css];
[javascript appendString:@"style.appendChild(cssContent);"];
[javascript appendString:@"document.body.appendChild(style);"];

// javascript注入
WKUserScript *noneSelectScript = [[WKUserScript alloc] initWithSource:javascript injectionTime:WKUserScriptInjectionTimeAtDocumentEnd forMainFrameOnly:YES];
WKUserContentController *userContentController = [[WKUserContentController alloc] init];
[userContentController addUserScript:noneSelectScript];
WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc] init];
configuration.userContentController = userContentController;

// WKWebView 初始化
WKWebView *webView = [[WKWebView alloc] initWithFrame:frame configuration:configuration];

---

另外提一句，获取webView当前选中的内容方法：

NSString *highlighted = [_webView stringByEvaluatingJavaScriptFromString:@"window.getSelection().toString();"];

参考链接：
http://blog.youkuaiyun.com/qq_30513483/article/details/51959187

http://www.cnblogs.com/sunshine-anycall/p/3245940.html

https://developer.apple.com/library/content/documentation/StringsTextFonts/Conceptual/TextAndWebiPhoneOS/AddingCustomEditMenuItems/AddingCustomEditMenuItems.html

http://notnull.hateblo.jp/entry/2015/05/15/134643

http://www.itdadao.com/articles/c15a265474p0.html

http://supereasyapps.com/blog/2014/4/17/show-the-uimenucontroller-and-display-custom-edit-menus-for-uiviewcontroller-uitableviewcontroller-and-uicollectionview-on-ios-7

http://www.jianshu.com/p/ddd59867909a