can anyone knows how to get a field in a custom record as dropdown value?

Do you mean you want to define a custom field as a dropdown on a custom record? If so you would define it as a List/Record type and specify either the list or record to use. If you mean you want to retrieve the value in script you would use

record.getValue({fieldId:'mycustomfield'});

to return the internal id or

record.getText({fieldId:'mycustomfield'});

to retrieve the text value.

hey thanks.. i did it.. but having one more doubt?

OK...

can we able to search a custom record in suitescript?

yes use the custom record id as the search type

thanks..

such:

yeah! i understand