Issue

The Mendix runtime and the client (UI/frontend) parse DateTime inputs differently, which leads to inconsistencies. For example, when a custom DateTime format is configured to be dd/MM/yyyy, but the input from a Date Picker is dd/MM/yy, then the runtime and the client will parse the year part differently:

• Runtime: 03/04/68 will be interpreted as 03/04/1968
• Client: 03/04/68 will be interpreted as 03/04/2068

Environment

Studio Pro (all versions)

Cause

The reason for the discrepancy is that the Mendix runtime follows a Java specification, whereas the Date Picker (client) follows a JavaScript library specification when interpreting DateTime.

Solution / Workaround

To ensure consistency, the application should contain logic to account for these differences by using Validation Rules, for example.

Additional information

Mendix documentation:

• Date Picker
• Validation Rules

Other documentation:

• Java SimpleDateFormat Specification
• date-fns JavaScript Library