meteor Blaze Templating Template Helpers
Example
Template helpers are an essential part of Blaze and provide both business logic and reactivity to a Template. It is important to remember that Template helpers are actually reactive computations that are rerun whenever their dependencies change. Depending on your needs, Template helpers can be defined globally or scoped to a specific template. Examples of each Template helper definition approach is provided below.
- Example of a Template helper scoped to a single template.
First define your template:
<template name="welcomeMessage">
<h1>Welcome back {{fullName}}</h1>
</template>
Then define the Template helper. This assumes that the data context of the template contains a firstName and lastName property.
Template.welcomeMessage.helpers({
fullName: function() {
const instance = Template.instance();
return instance.data.firstName + ' ' + instance.data.lastName
},
});
- Example of a global Template helper (this helper can be used from within any Template)
First register the helper:
Template.registerHelper('equals', function(item1, item2) {
if (!item1 || !item2) {
return false;
}
return item1 === item2;
});
With the equals helper defined, I can now use it within any template:
<template name="registration">
{{#if equals currentUser.registrationStatus 'Pending'}}
<p>Don't forget to complete your registration!<p>
{{/if}}
</template>
