This post is gives you some solutions for 10 real life application problems in asp.net:
How to interrupt postback from client side?
How to avoid duplicate form tag error?
How to ask confirmation on page unload event?
How to persists data from client to server side?
How to bind a dropdownlist from a datatable?
How to do a multi-line gridview?
How to serialize/deserialize object in XML?
How to enable disable validation from client side?
How to pass information between one page to another? [More]