v-bind Directive in Vue.js
The v-bind directive is a Vuejs directive used to bind one or more attributes, or a component prop to an element. If that attribute is binded to our data defined in Vuejs instance then dynamically changes can be observed as data changes. First, we will create a div element with id as app and let’s apply the v-bind directive to a element. Further, we can use a button execute a function when click even occurs which will inverse the value of data.
Syntax:
v-bind:attribute="expression";
Since developers use this attribute too often, Vuejs provides a shorthand for this attribute as follows:
:attribute="expression";
Things we can do with v-bind:
- Multiple classes can be passed.
- Classes can be passed as arrays.
- Supports variables to be assigned as a condition for classes and props.
- Supports variable as arrays also.
- It can be used in child components also.
- Inline styles can also be assigned using v-bind.
Parameters: This directive accepts expression which will be deciding which attribute value to use.
Example: This example uses Vuejs to toggle the classes of an element with v-bind. Further, we will use CSS to apply a different color to each class so that we can see them changing.
HTML
<!DOCTYPE html><html><head> <!-- Load Vuejs --> <script src= </script> <style> .active { color: blue; } .error { color: red; } </style></head><body> <div style="text-align: center;width: 600px;"> <h1 style="color: green;"> GeeksforGeeks </h1> <b> VueJS | v-bind directive </b> </div> <div id="canvas" style= "border:1px solid #000000; width: 600px;height: 200px;"> <div id="app" style= "text-align: center; padding-top: 40px;"> <button v-on:click= "ifActive = !ifActive"> Click to Toggle </button> // here we have used the : short hand of v-bind: <h1 :class= "{active: ifActive, error: !ifActive}"> GeeksforGeeks </h1> </div> </div> <script> var app = new Vue({ el: '#app', data: { ifActive: true } }) </script></body></html> |
Output:
Please Login to comment...