CODEWITHSUNDEEP
grails
Chapsterj
Chapsterj

Reputation: 6625

How to extract the first value in a grails object

I have a grails object that I want to extract the first value in it. I'm new to grails and not understanding the language fully yet. I used a loop to extract them before but this time I just need the first value and nothing else. I tried just using 

<div id="blaa">${items}[0].value"</div>

That threw an error.

Below is usually how I would loop through the object.

             <g:each in="${items}" var="item" status="i">
                    <li><a href="#">${item.value}</a></li>
                </g:each>

Upvotes: 2

Views: 1257

Answers (3)

saurabh
saurabh

Reputation: 151

You can use ${items.head().value} to get the first value

Upvotes: 0

cdeszaq
cdeszaq

Reputation: 31280

While @Gregg's answer is correct and will allow you to get the first element, there is an easier way and it's very close to what you tried:

<div id="blaa">${items[0].value}"</div>

The issue is that you need to have all of your "code" pieces within the ${...} structure. Everything outside of that is just treated as a string.

As long as items is an ordered Collection (so, a List, a Map, or a Range, but not a Set), you can access it like an array in Groovy (the language Grails is built in). @Gregg's answer explicitly converts items to an array first and then accesses it like an array.

Upvotes: 2

Gregg
Gregg

Reputation: 35864

Making some assumptions here because you're not showing a lot of code and you also didn't tell us the error:

By default collections in Grails are Sets. To get the first value in a set you could do something like:

${item.toArray()[0]}

Upvotes: 1

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