TAILIEUCHUNG - Professional ASP.NET 1.0 Special Edition- P3
Professional Special Edition- P3:Those of us who are Microsoft developers can't help but notice that .NET has received a fair amount of visibility over the last year or so. This is quite surprising considering that for most of this period, .NET has been in its early infancy and beta versions. I can't remember any unreleased product that has caused this much interest among developers. And that's really an important point, because ignoring all the hype and press, .NET really is a product for developers, providing a great foundation for building all types of applications | The left-pane shows all of the types matched. The right side shows the type definition retrieved using the reflection classes. Using the information shown we can determine that the HttpRequest class is defined as part of the namespace which is contained in the file . By now you should have a fairly good picture of how the .NET Framework fits together so let s look at some of the design goals and see how the .NET Framework was used to build . Design Goals To understand some of the reasons why works the way it does we ll cover some of the key design goals of in this section. We ll be looking at these in more depth later in the book. Some of the key goals of were to Remove the dependency on script engines enabling pages to be type safe and compiled. Reduce the amount of code required to develop web applications. Make well factored allowing customers to add in their own custom functionality and extend replace built-in functionality. Make it easy to deploy web applications. Make a logical evolution of ASP where existing ASP investment and therefore code can be reused with little if any change. Provide great tool support in terms of debugging and editing. Realize that bugs are a fact of life so should be as fault tolerant as possible. We ll examine each of these goals and look at how they have been realized in . Remove the Dependency on Script Engines ASP is built using Active Scripting a technology originally designed to enable developers to script and control applications in a uniform way. It isn t a technology that was really designed to write full-scale applications which is essentially what many developers are trying to do using ASP which is why was not written using Active Scripting. Active Scripting has many inherent problems Code is interpreted not compiled It has a weak type system - just variants It only supports late-bound calling of methods .
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