detection

问题 In this question I did not see suggestions to use constructor. So instead of typeof callback == "function" I would use callback && (callback.constructor==Function) . To me it seems obvious that comparison to memory pointers is always better than comparison to strings in terms of both runtime performance and coding safety. Why not use constructor to detect all types and forget about ugly typeof ? It works for all primitive types, functions and arrays: undefined === undefined null === null [1,2

问题 I have created a script which detects installed .Net Framework installed through registry. The condition should specifically detect 3.5 or higher version and continue the process. However, using the registry it seems not possible. Every time there is a new version installed, you have to search and input the registry or modify the script just to make it works. Then I searched it up on google that it can be done through WMI and this seems gonna work. I have modified the script to be flexible

问题 I am trying to make a rotate a hitbox that detects collision. I want a non-rotating rectangle_1 moving from the left to the right and a rotating rectangle_2 moving from the right to the left, and I want the rotating hitbox to detect the collision regardless of its orientation. However, collision is detected only when rectangle_1 collides with the non-rotated rectangle_2. How can I make a rotating hit box detect collision? Here are the codes: The main program: import java.awt.Color; import

问题 I have a framework which had all beacon detection logic and a sample app which sets up and tears down framework. I want to get region enter and exit notifications after app is killed. I am able to get notifications from app when logic is in app. But when the logic is in framework I don't get notifications. What am I doing wrong? import UIKit import CoreLocation extension AppDelegate: CLLocationManagerDelegate { func registerForBeaconNotifications() { let locationManager = CLLocationManager()

问题 I develope a Chrome extension. I want to detect a download before the actual download has started. There is a chrome.downloads API but all events are fired too late. There is also a webRequest API with a lot events. Sadly the data provided by those events didn't help me to detect a download (request). Is there any possibility to detect a download BEFORE chrome already downloads a file? 来源： https://stackoverflow.com/questions/34152836/is-it-possible-to-detect-a-download-before-the-actual

问题 I need to run a module that need ssl to be enabled. How can I detect if ssl has been enabled? The module generate a form through a javascript call. I am using php. I have no access to ssl . Thanks a lot! 回答1: use the extension loaded check! http://php.net/manual/en/function.extension-loaded.php if(!extension_loaded('openssl')) { throw new Exception('This app needs the Open SSL PHP extension.'); } try it ;) 来源： https://stackoverflow.com/questions/21848277/check-if-ssl-is-enabled-with-php

问题 Is there are any way to detect the change of time in getCurrentTime() of YouTube API? Purpose:To play single video for limited time(<1 min) in my page and move on to next video. I was thinking to use object.watch but it only works for the variables not the functions. I also try to bind something in the original source code https://s.ytimg.com/yts/jsbin/www-widgetapi-vfl9twtxR.js but it was too complicated. 回答1: Because the YouTube player is wrapped in an iFrame, you are dependent on what the

问题 I've been working off a variant of the opencv squares sample to detect rectangles. It's working fine for closed rectangles, but I was wondering what approaches I could take to detect rectangles that have openings ie missing corners, lines that are too short. I perform some dilation, which closes small gaps but not these larger ones. I considered using a convex hull or bounding rect to generate a contour for comparison but since the edges of the rectangle are disconnected, each would read as a

问题 provided a DIV with fixed heigh disabled scrolling feature whose content is editable I need to understand if its content height as reached or even exceeded the height of the same div according to the element (text or other) inserted by the user (control triggered on event basis). Does anybody have any simple idea how to detect if the content of a DIV has reached or even exceeded the height of the same DIV? 回答1: As stian said in their answer, you can use jQueries height() method to obtian the

问题 I want to let my script check, if a specific tab is open or not in google chrome, for example "https://stackoverflow.com/". I know how to check if the browser runs at all, but I am not sure, if it's possible to let check it if an specific tab is open. Does someone has an idea, how i could realize this? 回答1: Sort of.. First you need OpenList extension for chrome.Then you need snedkeys.bat. This is a script in the same directory as the snedKeys.bat.It will list all opened links in chrome: @echo