Hi! Jigeesha,

Thanks for your question. You can provide validation in your  domain model. I share this screenshot. You can also edit the validation rules in the entity in the domain model. For example, you can choose an attrubute validation rules required type, then you are doing Name attribute required validation. Also, you can set your e-mail adress by choosing rule type regular expression. https://docs.mendix.com/refguide/validation-rules/ You can find validation rules Mendix documentation on this link. I hope you have solved this problem.

Have a great day! Success with Mendix! 

Kind regards,

Mehmet

Hi Jigeesha,

You can add the validation in the settings of the reference set selector or you can create an events  Microflow that validates the input of the reference selector.

Hi Jigeesha Boddeda,

       You can add validation through microflow. 
  

on Save Microflow Validation → Check and through validation message in false flow.

Good Luck.

Well I assume that you need validation for that on a page 

 If you are saving something then Automatically you will have that parameter in Microflow

So Instead of “Save Changes” Do it with “Call a Microflow” for the save button 

Put a simple decision in the microflow 

Call the association in that decision , If empty then put a validation feedback else , Commit the object (whatever is the parameter). So by this method you can add validation on any part of the page.