Dynamic Default Question Values

SurveyJS Form Library allows you to specify default question values. Questions use them until proper values are specified by a user or programmatically. If the proper values are never specified, default values are saved in survey results.

You can specify static default values or calculate default values dynamically. To specify a static default question value, assign it to the question's defaultValue property.

To calculate a default question value dynamically, assign a logical expression to the question's defaultValueExpression property as shown in this demo. This expression will be evaluated for the first time when the survey begins, and then re-evaluated again each time any question value changes. Your expression can include the following dynamic elements:

• Question values
• Variables
• Calculated values
• Built-in functions
• Custom JavaScript functions

Follow the links above for information on how to use these elements to specify dynamic default question values.