Modify query string values of current page (hashmap)- dotCMS

## Get the query string as a hashmap
## NOTE: Things will break if you use some special characters (""","&", etc. )
#set($queryParams = $contents.getEmptyMap())
#foreach($key in $request.getParameterNames())
	#set($value = $request.getParameter($!{key}))
	#set($key = $key.replaceAll("[^a-zA-Z0-9]",""))
	## #set($queryParams.y = ${value})
	$render.eval("${esc.h}set(${esc.d}queryParams.${key} = ${esc.d}{value})")
#end


## Convert query string hashmap back to a query string ($queryString)
#macro(toQueryString $queryMap)
	#set($queryString = "")
	#foreach($item in $queryMap.entrySet())
		#if($velocityCount == 1)
			#set($joiner = "?")
		#else
			#set($joiner = "&")
		#end
		#set($value = $UtilMethods.encodeURL($item.value))
		#set($queryString = "${queryString}$!{joiner}${item.key}=${value}")
		#set($value = "")
		#set($joiner = "")
	#end
#end

## Example usage:
## Clone the existing query string data, make changes to it,
## then put it back in a query string for the current page

#set($queryParams2 = $queryParams.clone())
#set($queryParams2.y = "2015")
#toQueryString($queryParams2)
<a href="${VTLSERVLET_URI}$!{queryString}">Link</a>