You are posting number of question with title 'Question regarding ASP.NET'. You should read on the way question should be posted before posting it. Read here:
http://www.codeproject.com/Questions/ask.aspx[
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Your title should be short and sweet related to what you ask.
You need to tag it correctly to ASP.NET if it is related to that
You need to use comment feature using 'having a Question or comment' link to discuss an answer instead of posting a new question as a followup
You should frame your question properly with details on what and why you are doing something and where are you stuck.
Now, even if you have multiple fields, required field validator for every field is OK. In case you are skeptical on using them then you at the time of page submit, call a JS method where check all the input field values. If any one is empty and is required then show an alert and stop submit of the page.
Try out and now ask specific question.
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