class ExamplesTagLib {
def showParameter = {
out << "Parameter id has the value ${params['id']}"
}
}params
Purpose
A mutable multi-dimensional map (hash) of request (CGI) parameters.
Examples
To obtain a request parameter called id:
<g:showParameter />Description
The standard Servlet API provides access to parameters with the HttpServletRequest object. Although Grails provides the same capability through the request object, it goes a bit further by providing a mutable map of request parameters called params.
The params object can be indexed into using the array index operator or de-reference operator, so given the URL /hello?foo=bar you can access foo with
params['id']
The params object can also be used to bind request parameters onto the properties of a domain class using either the constructor or the properties property: