Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

How to get index in Handlebars each helper?

People also ask

What is helper in handlebars?

A Handlebars helper call is a simple identifier, followed by zero or more parameters (separated by a space). Each parameter is a Handlebars expression that is evaluated exactly the same way as described above in "Basic Usage": template {{firstname}} {{loud lastname}}

What is handlebars template?

Handlebars is a simple templating language. It uses a template and an input object to generate HTML or other text formats. Handlebars templates look like regular text with embedded Handlebars expressions.

Can you use handlebars in Javascript?

Handlebars. js is a Javascript library used to create reusable webpage templates. The templates are combination of HTML, text, and expressions. The expressions are included in the html document and surrounded by double curly braces.


In the newer versions of Handlebars index (or key in the case of object iteration) is provided by default with the standard each helper.


snippet from : https://github.com/wycats/handlebars.js/issues/250#issuecomment-9514811

The index of the current array item has been available for some time now via @index:

{{#each array}}
    {{@index}}: {{this}}
{{/each}}

For object iteration, use @key instead:

{{#each object}}
    {{@key}}: {{this}}
{{/each}} 

This has changed in the newer versions of Ember.

For arrays:

{{#each array}}
    {{_view.contentIndex}}: {{this}}
{{/each}}

It looks like the #each block no longer works on objects. My suggestion is to roll your own helper function for it.

Thanks for this tip.


In handlebar version 3.0 onwards,

{{#each users as |user userId|}}
  Id: {{userId}} Name: {{user.name}}
{{/each}}

In this particular example, user will have the same value as the current context and userId will have the index value for the iteration. Refer - http://handlebarsjs.com/block_helpers.html in block helpers section


I know this is too late. But i solved this issue with following Code:

Java Script:

Handlebars.registerHelper('eachData', function(context, options) {
      var fn = options.fn, inverse = options.inverse, ctx;
      var ret = "";

      if(context && context.length > 0) {
        for(var i=0, j=context.length; i<j; i++) {
          ctx = Object.create(context[i]);
          ctx.index = i;
          ret = ret + fn(ctx);
        }
      } else {
        ret = inverse(this);
      }
      return ret;
}); 

HTML:

{{#eachData items}}
 {{index}} // You got here start with 0 index
{{/eachData}}

if you want start your index with 1 you should do following code:

Javascript:

Handlebars.registerHelper('eachData', function(context, options) {
      var fn = options.fn, inverse = options.inverse, ctx;
      var ret = "";

      if(context && context.length > 0) {
        for(var i=0, j=context.length; i<j; i++) {
          ctx = Object.create(context[i]);
          ctx.index = i;
          ret = ret + fn(ctx);
        }
      } else {
        ret = inverse(this);
      }
      return ret;
    }); 

Handlebars.registerHelper("math", function(lvalue, operator, rvalue, options) {
    lvalue = parseFloat(lvalue);
    rvalue = parseFloat(rvalue);

    return {
        "+": lvalue + rvalue
    }[operator];
});

HTML:

{{#eachData items}}
     {{math index "+" 1}} // You got here start with 1 index
 {{/eachData}}

Thanks.


Arrays:

{{#each array}}
    {{@index}}: {{this}}
{{/each}}

If you have arrays of objects... you can iterate through the children:

{{#each array}}
    //each this = { key: value, key: value, ...}
    {{#each this}}
        //each key=@key and value=this of child object 
        {{@key}}: {{this}}
        //Or get index number of parent array looping
        {{@../index}}
    {{/each}}
{{/each}}

Objects:

{{#each object}}
    {{@key}}: {{this}}
{{/each}} 

If you have nested objects you can access the key of parent object with {{@../key}}


Using loop in hbs little bit complex

<tbody>
     {{#each item}}
         <tr>
            <td><!--HOW TO GET ARRAY INDEX HERE?--></td>
            <td>{{@index}}</td>
            <td>{{this}}</td>
         </tr>
     {{/each}}
</tbody>

Learn more