mirror of
https://github.com/gohugoio/hugo.git
synced 2024-11-29 16:52:10 -05:00
5fd1e74903
``` git subtree add --prefix=docs/ https://github.com/gohugoio/hugoDocs.git master --squash ``` Closes #11925
45 lines
1.2 KiB
Markdown
45 lines
1.2 KiB
Markdown
---
|
|
title: collections.IsSet
|
|
description: Reports whether the key exists within the collection.
|
|
categories: []
|
|
keywords: []
|
|
action:
|
|
aliases: [isset]
|
|
related:
|
|
- functions/go-template/if
|
|
- functions/go-template/with
|
|
returnType: bool
|
|
signatures: [collections.IsSet COLLECTION KEY]
|
|
aliases: [/functions/isset]
|
|
---
|
|
|
|
For example, consider this site configuration:
|
|
|
|
{{< code-toggle file=hugo >}}
|
|
[params]
|
|
showHeroImage = false
|
|
{{< /code-toggle >}}
|
|
|
|
It the value of `showHeroImage` is `true`, we can detect that it exists using either `if` or `with`:
|
|
|
|
```go-html-template
|
|
{{ if site.Params.showHeroImage }}
|
|
{{ site.Params.showHeroImage }} → true
|
|
{{ end }}
|
|
|
|
{{ with site.Params.showHeroImage }}
|
|
{{ . }} → true
|
|
{{ end }}
|
|
```
|
|
|
|
But if the value of `showHeroImage` is `false`, we can't use either `if` or `with` to detect its existence. In this case, you must use the `isset` function:
|
|
|
|
```go-html-template
|
|
{{ if isset site.Params "showheroimage" }}
|
|
<p>The showHeroImage parameter is set to {{ site.Params.showHeroImage }}.<p>
|
|
{{ end }}
|
|
```
|
|
|
|
{{% note %}}
|
|
When using the `isset` function you must reference the key using lower case. See the previous example.
|
|
{{% /note %}}
|