XPO:
XPO between the application code and database plays the role of an intermediate layer, simply, is object-oriented programming object created to do a mapping in the database, making it one to one relationship and the establishment of a database table . XPO current version can handle dealing with the relationship of one to many, many to many, etc. between objects, inheritance achieve in the database as well as concurrent access database processing according to the situation, improve the efficiency of the system.
The greatest advantage is that you can XPO application developers from the tedious database design came out, concentrate on the establishment of a business object system, how to map these objects to the database, all this can be handled automatically to the XPO.
WCF:
WCF just the specific "to achieve" written in the "Service end" and "call" on the "Client-side."
Web Service
1, which is based on the SOAP protocol, data format is XML
2, only supports HTTP protocol
3, it is not open source, but can be any person to use an understanding of XML
4, it can only be deployed on IIS
WCF
1, this is a SOAP-based, data format is XML
2, this is a Web Service (ASMX) evolutionary version, it can support a variety of protocols, such as TCP, HTTP, HTTPS, Named Pipes, MSMQ.
3, WCF main problem is that it's cumbersome to configure up special
4, it is not open source, but can be any person to use an understanding of XML
5, it can be deployed in an application or on IIS or Windows Service
Common Intermediate Language Common Intermediate Language CIL previous name is called Microsoft Intermediate Language MSIL or IL
Global Assembly Cache Global Assembly Cache, GAC
Just-In-Time JIT compiler
Once you've created the array size is usually fixed and can not add a new item to the end of an existing array.
Array: only with a fixed size array initialization Animal [] animals = new Animal [2];
ArrayList set not need to initialize its size: ArrayList arrayList = new ArrayList ();
Initialize the array items:
Cow myCow1 = new Cow("Lea");
animals[0] = myCow1;
animals[1] = new Chicken("Noa");
ArrayList uses its own method for increasing the Add New Item
Cow cow = new Cow("Rual");
arrayList.Add(cow);