this.timer = setTimeout(function() { this.clearBoard(); // what is "this"? }, 0); }; 执行上面的代码会导致以下错误:“Uncaught TypeError: undefined is not a function。” 发生以上错误的原因是,当你调用 setTimeout( ) 时,实际上是在调用 window.set
If you're using the compiled (or minified) bootstrap.js, there is no need to include this—it's already there. What's inside Transition.js is a basic helper for transitionEnd events as well as a CSS transition emulator. It's used by the other plugins to check for CSS transition ...
(2)接下来运行console.log("hi"),该函数没有调用任何其他函数。 (3)然后继续执行下面的setTimeout,setTimeout是一个异步函数,经过5秒之后,在运行队列里面插入这个回调函数,然后如果该队列之前没有其他函数,就执行该队列,有则等待前面的函数执行完成,再执行。 (4)console.log("My Name Is Chirs")不会等待5s之...
("Clearing local storage..."); };this.clearBoard=function() {console.log("Clearing board..."); }; };Game.prototype.restart=function() {this.clearLocalStorage();this.timer=setTimeout(function() {this.clearBoard();// What is "this"?},0); };constmyGame =newGame(); myGame.restart(...
JavaScript is free to use for everyone.JavaScript ExercisesMany chapters in this tutorial end with an exercise where you can check your level of knowledge.Exercise? What is a correct syntax for assigning a value to a variable? x : 5 x = 5 x == 5 x -> 5Submit Answer »See...
To tweak what's considered "slow", you can use the slow() method: describe('something slow', function() { this.slow(300000); // five minutes it('should take long enough for me to go make a sandwich', function() { // ... }); }); ...
JavaScript is a structurally typed language where objects are compatible if they share the same structure (i.e., the same set of properties and methods).Duck Typing: This is a concept where an object's suitability is determined by the presence of certain properties and methods, rather than ...
Publish your appExplore AppSource Office developer resources Documentation Read docs Code Download samples Community calls Add to calendar Blogs Stay current Microsoft Q&A forum Ask a question Suggestions Request a feature What's new in Office Add-ins ...
What is the order of precedence if more than one rule matches a call site? If the function was called with thenewkeyword,thiswould point to the newly created object. If it was called with any of these—call(),apply()orbind()—use the specified context object as the value ofthis. ...
Blend modes are used to blend layers together to create an interesting effect in a layer, or even to produce what seems like a new layer. Unlike the method of using transparency which can result in a washed-out top layer, blend modes can create a variety of very vibrant and intriguing re...