What is QueryString? What are the advantages and disadvantages of QueryString?

QueryString is a property of Request object in ASP.Net that provides a mechanism to send information to the server in the form of Sting in the URL.

Example: http://www.testsite.com/Webform1.aspx?fname=Alok&lname=Ranjan

In the above example, the destination webform name is Webform1.aspx and the information passed in QueryString is fname=Alok&lname=Ranjan. fname is a variable whose value is Alok, and similarly lname variable has value as Ranjan.

Advantages of QueryString:

• It's very easy to implement
• Every browser works with QueryString.
• It doesn't require server resources. Hence, doesn't put any burden on Server.

Disadvantages of QueryString:

• There is a limitation in the length of the QueryString as URL length has a limit. If you have to send lot of information, QueryString approach doesn't work.
• The information passed through QueryString is publicly visible. Hence, it poses security issue. So, QueryString can't be used while sending sensitive info. 
• QueryString can not be used to send & and space characters.