Download multiple files at once in one HTTP Request in ASP.Net using C# and VB.Net

Here Mudassar Ahmed Khan has explained with an example and attached sample code, how to download multiple files at once in one HTTP Request in ASP.Net using C# and VB.Net. HTTP Response does not allow multiple files to be downloaded and hence the solution is to compress and zip multiple files into a single Zip Archive file using the DotNetZip Library in ASP.Net using C# and VB.Net.