Conditional logic in Vue.js

Is there any way to add conditional logic to a string template in Vue.js? This is what I tried however compiling fails.

<div v-for="foo in foos">
    {{#if foo.bar === 1}}
        {{foo.name}}
    {{/if}}
</div>

Answer

You have to use v-if directive.

v-if is “real” conditional rendering because it ensures that event listeners and child components inside the conditional block are properly destroyed and re-created during toggles.

<div v-for="foo in foos" v-if="foo.bar===1">
    {{foo.name}}
</div>

Read more about in this documentation.

var demo = new Vue({
    el: '#demo',
    data: {
       items:[{
      id:1,
      message:'message1'
    },{
      id:2,
      message:'message2'
    }]
    }
})

<script src="https://vuejs.org/js/vue.min.js"></script>
<div id="demo">
   <div v-for="item in items" v-if="item.id==1">
     {{item.message}}
   </div>
</div>

Also, you can use a computed method. See reference here.

var demo = new Vue({
    el: '#demo',
    data: {
       items:[{
      id:1,
      message:'message1'
    },{
      id:2,
      message:'message2'
    }]
    },
    computed: {
      myMethod: function () {
        return this.items.filter(function (item) {
          return item.id === 1
        })
    }
}
})

<script src="https://vuejs.org/js/vue.min.js"></script>
<div id="demo">
   <div v-for="item in myMethod">
      {{item.message}}
   </div>
</div>