Vue.js | v-if directive

Last Updated : 22 Jun, 2020

The v-if directive is a Vue.js directive used to toggle the display CSS property of a element with a condition. If the condition is true it will make it visible else it will make it invisible. First, we will create a div element with id as app and let's apply the v-if directive to this element with data. Now we will create this data by initializing a Vue instance with the data attribute containing the value.

Syntax:

v-if="data"

Parameters: This directive accepts a single parameter which is the data or a condition.
Example 1: This example uses VueJS to show an element with v-if.

HTML

<!DOCTYPE html>
<html>

<head>
    <title>
        VueJS | v-if directive
    </title>

    <!-- Load Vuejs -->
    <script src=
"https://cdn.jsdelivr.net/npm/vue/dist/vue.js">
    </script>
</head>

<body>
    <div style="text-align: center;width: 600px;">
        <h1 style="color: green;">
            GeeksforGeeks
        </h1>
        <b>
            VueJS | v-if directive
        </b>
    </div>

    <div id="canvas" style="border:1px solid #000000;
                            width: 600px;height: 200px;">
        <div id="app">
            <h2 v-if="message">
              This if condition is executed
            </h2>
        </div>
    </div>

    <script>
        var app = new Vue({
            el: '#app',
            data: {
                message: true
            }
        })
    </script>
</body>
</html>

Output:

Example 2: This example uses VueJS to show an element with v-if arithmetic conditions.

HTML

<!DOCTYPE html>
<html>

<head>
    <title>
        VueJS | v-if directive
    </title>

    <!-- Load Vuejs -->
    <script src=
"https://cdn.jsdelivr.net/npm/vue/dist/vue.js">
    </script>
</head>

<body>
    <div style="text-align: center;width: 600px;">
        <h1 style="color: green;">
            GeeksforGeeks
        </h1>
        <b>
            VueJS | v-if directive
        </b>
    </div>

    <div id="canvas" style="border:1px solid #000000;
                            width: 600px;height: 200px;">
        <div id="app">
            <h2 v-if="a > 10">a is greater than 10</h2>
            <h2 v-if="a < 10">a is smaller than 10</h2>
            <h2 v-if="a == 10">a is equal to 10</h2>
        </div>
    </div>

    <script>
        var app = new Vue({
            el: '#app',
            data: {
                a: 9
            }
        })
    </script>
</body>
</html>