We could even update the function to accept parameters, and pass them like so:What that means, is that we can call any function, and These built in methods, that exist on every JS function can be very useful. If you'd like to contribute to the interactive examples project, please clone The compatibility table on this page is generated from structured data. If you haven’t already created an account, you will be prompted to do so after signing in. 调用绑定函数时作为 this 参数传递给目标函数的值。 如果使用new运算符构造绑定函数，则忽略该值。当使用 bind 在 setTimeout 中创建一个函数（作为回调提供）时，作为 thisArg 传递的任何原始值都将转换为 object。如果 bind 函数的参数列表为空，执行作用域的 this 将被视为新函数的 thisArg。 arg…
Let’s begin with the Bind method. call and apply will call a function immediately letting you specify both the value of this and any arguments the function will receive.. However, with data binding we may use a separate source, like a database, an XML file, or a script to fill the list with selectable items. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. w3schools - javascript metodo bind . The source for this interactive example is stored in a GitHub repository.
bind() returns a bound function that, when executed later, will have the correct context ("this") for calling the original function. Examples might be simplified to improve reading and basic understanding. [[BoundThis]] - the value that is always passed as this value when calling the wrapped function. call() or Function.prototype.call() the JS engine is creating a new pokemonName instance and binding pokemon as its this variable. The JavaScript Function bind() method is used to create a new function. By data binding to the DOM I mean for example, having a JavaScript object a with a property b. Call( ), Bind( ), and Apply( ) to Rescue. Only one way to find out...When you bind a function, you ask for a new function that ignores it's own this pseudo argument and calls the original function with a fixed value for this.Binding this function another time has exactly the same behaviour. However, bind does not modify anything, it creates a new function with specific behaviour. 3. The bind() method attaches one or more event handlers for selected elements, and specifies a function to run when the event occurs. It is usually used when you want to pass a function to an event handler or other async callback. To fix that, jQuery.each would have to specialcase bound functions somehow. These 3 Function methods are workhorses and sometimes you absolutely need one of them. Chris Leary, who works on Mozilla's JS engine (as I do), thought it a bit odd, raising the issue on Twitter a couple months ago. Until now we have only been talking about binding this. Don’t worry! Then having an DOM element (for example), when the DOM element changes, a changes and vice versa (that is, I mean bidirectional data binding). We can bind not only this, but also arguments. Data binding in AngularJS synchronizes AngularJS expressions with AngularJS data. Das Erzeugen einer neuen Wrapper-Funktion, die eine andere mit vordefinierten Parametern aufruft, nennt sich Currying . bind returns a function which will act like the original function but with this predefined. The bind() method was deprecated in version 3.0. While Apply and Call come with ECMAScript 3 (available on IE 6, 7, 8, and modern browsers), ECMAScript 5 (available on only modern browsers) added the Bind method. Usually when you use bind, you do it this way:Okay so that's cool, but what is suppose to happen when we do this?I understand that it's completely logical behavior in terms of how Function.prototype.bind is implemented (To make it more clear, what in my opinion would make more sense, here is the code snippet that implements Function.prototype.bind a little bit differently:In my opinion, replacing "this" makes more sense...You're not the only person I've heard who thought this odd. I will now walk through these 3 similar methods that appear on every function with examples.