asp.net mvc 3 - Where i need to put validation code? -

i have form number of fields.

some of them userid, userfirstname, userlastname.

when user inputs incorrect userid value near userid field page must show error message , add error validationsummary(this standart behavior asp.net mvc unobtrusive validation). if userid correct page must remove errors , autopopulate userfirstname , userlastname(this not standart behavior)

how can implement this?

here come mind:

1. remote validation attribute

   it has bad customization in case. that's why decide don't use it.

2. add special method jquery validation plugin ( example

   jquery.validator.addmethod("useridvalidation", function(value, element) { //some logic return something; }, "please specify correct userid"); )

and put there logic validation , autopopulate other fields. in case mix validation , other stuff.

3 . add special method jquery validation plugin validation , add special handler input change event autopopulate.

in case need send 2 ajax requests server 1 thing. , ofcourse not too. right way? confused.

have thought using partial view display userfirstname , userlastname?

you can fire ajax request sends userid, , returns partial view of name fields. within controller being called, can validate incoming userid, , grab name details in 1 query. if thevalidation fails, can return partial view empty fields.