I have a multiselect combobox in my extJS form.

It returns an array of strings on submit.

I want to convert it the array to json(in a particular format).

Eg. It returns in the following array:

```
categories : ['ABC','XYZ']

```

I want the JSON in the following format:

```
"categories":[{"name":"ABC"},{"name":"XYZ"}]

```

Are there any methods in ExtJs to do this?
How to achieve this using javascript?