url_param

To populate data from a URL parameter into a data field, use the url_param method. Unlike getParm, url_param will work on any page to populate data included in a survey entry link via a URL parameter into a survey variable as long as the reference is correctly formulated. This is possible because the url_param method is not looking at the current page URL. Rather, it is looking at the system variable 'entry_url' which by default captures and stores the link the respondent uses to enter the survey, parameters and all. This allows for far greater flexibility than getParm with regards to populating survey data. Additionally, url_param is not case sensitive. So, in the event that a panel provider uses all upper case, all lower case, or some combination thereof in the url parameter label that you must capture, url_param will be successful.

Examples

To grab information from a survey entry link URL using url_param, you must set up a variable to capture it and store it. Each individual parameter needs a question to capture the value. The type of data being passed in will determine the type of variable you need to capture it. Use the url_param expression with dvalue or cvalue to match and store the value from the parameter in the URL with the same name. In the examples below the letter 'n' is used for the "first name" parameter, and the word 'pan' is used for the "panel" parameter.

Open-end data

To capture open-end data, for instance letters like in a name, use a type: text question to capture and store a string:

# Entry URL example
# http://servername.intellisurvey.com/pub/survey_ID/record_ID?n=Jeff

F_NAME. Respondent First Name Passed In
invisible: y
type: text
cvalue: url_param('n')

Closed-end data

To capture closed-end data, for instance a numeric value, use a type: radio question where each number can be used to classify information:

# Entry URL example
# http://servername.intellisurvey.com/pub/survey_ID/record_ID?pan=1

PANEL. Panel Identifier
invisible: y
type: radio
cvalue: url_param('pan')
1. Panel 1
2. Panel 2

Usage with multi-select variables

url_param can also punch multiple options with a type: checkbox question. You have to pass each parameter one at a time by repeating the parameter in the entry URL (invite links) as shown below. In this example, QPRODUCT will punch both options 1 and 3, or Toaster oven and Blender, respectively.

# Entry URL example
# http://servername.intellisurvey.com/pub/survey_ID/record_ID?t=1&t=3
 
PRODUCT. Products Purchased
type: checkbox
invisible: y
cvalue: url_param('t')
1. Toaster oven
2. Microwave
3. Blender
 
setconditionedtext: PURCHASE
1. purchase {if countChecked($QPRODUCT) == 1}
2. purchases {if countChecked($QPRODUCT) > 1}
 
newpage
 
This survey will ask about your recent [* lc get_phrase('QPRODUCT') *] __PURCHASE__.

Conditional syntax

As with any cvalue expression, url_param can be used with conditional syntax ("if" and "else" statements). In the following example, option 99 is punched if the 'pan' parameter is absent from the URL. 

PANEL. Panel Identifier
invisible: y
type: radio
cvalue: if (url_param('pan')) {url_param('pan')} else {99}
1. Panel 1
2. Panel 2
99. No Panel Specified