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==== Reading Messages in the View


The most common place that you need messages is inside the view. Use the link:{gspTagsRef}message.html[message] tag for this:

[source,xml]
----
<g:message code="my.localized.content" />
----

As long as you have a key in your `messages.properties` (with appropriate locale suffix) such as the one below then Grails will look up the message:

[source,groovy]
----
my.localized.content=Hola, me llamo John. Hoy es domingo.
----

Messages can also include arguments, for example:

[source,xml]
----
<g:message code="my.localized.content" args="${ ['Juan', 'lunes'] }" />
----

The message declaration specifies positional parameters which are dynamically specified:

[source,groovy]
----
my.localized.content=Hola, me llamo {0}. Hoy es {1}.
----

==== Reading Messages in Grails Artifacts with MessageSource

In a Grails artifact, you can inject `messageSource` and use the method `getMessage` with the arguments: message code, message arguments, default message and locale to retrieve a message.

[source,groovy]
----
import org.springframework.context.MessageSource
import org.springframework.context.i18n.LocaleContextHolder

class MyappController {

    MessageSource messageSource

    def show() {
        def msg = messageSource.getMessage('my.localized.content', ['Juan', 'lunes'] as Object[], 'Default Message', LocaleContextHolder.locale)
    }
----

==== Reading Messages in Controllers and Tag Libraries with the Message Tag

Additionally, you can read a message inside Controllers and Tag Libraries with the link:{gspTagsRef}message.html[Message Tag]. However, using the message tag relies on GSP support which a Grails application may not necessarily have; e.g. a rest application.

In a controller, you can invoke tags as methods.

[source,groovy]
----
def show() {
    def msg = message(code: "my.localized.content", args: ['Juan', 'lunes'])
}
----

The same technique can be used in link:theWebLayer.html#taglibs[tag libraries], but if your tag library uses a custom link:theWebLayer.html#namespaces[namespace] then you must prefix the call with `g.`:

[source,groovy]
----
def myTag = { attrs, body ->
    def msg = g.message(code: "my.localized.content", args: ['Juan', 'lunes'])
}
----
