答案僅供參考，歡迎交流質疑。
一、選擇題
2. The smallest unit for deployment in C# is called _______.
A.Assembly B.Namespace C.Package D.Modole
Assembly is the smallest unit for deployment and dynamic loading
the smallest unit for versioning3. Not a valid indetifier _______.
A.@do B._main_ C.in D.πλα
In是C#關鍵字；可以以π、字母下劃線開頭
@+關鍵字也可以。
4. How to assign a char-type variable c with a single quote character _______.
A.c=”’” B.c=’\”’ C.c=’\’’ D.c=\’
轉義符
5. How many bytes will an int type variable usually take on 64-bit machines? _______
A.2 B.4 C.8 D.16
佔4字節，32位
8. “enum color:byte{Red,Yellow,Blue,Green,Purple};”, then “(Color.Yellow & Color.Blue” is _______.
A.Color.Red B.Color.Green C.Color.Purple D.null
9. How do you format a float numble x only showing 3 numbles after the dot with an 8 character width?
A.”{1:f3}”,x B.”{1,8:f}” ,x C.”{1,8:f3}”,x D.”{0,8:f3}”,x
索引必須從0開始
二、判斷題
1. Multiple catch blocks are allowed after one try block. T
2. String type variables are legal as branch values in switch structure. T
C#中string可以作爲分支判斷值
sbyte、byte、short、ushort、int、uint、long、ulong、char、string +枚舉類型
3. File name and the main class name in that file need to be identical. F
不一定要相同
4. All methods in an abstract class must be declared as abstract methods. F
一個抽象類可以有抽象方法，也可以有非抽象方法
5. One method can only have one variable-length parameter. T
6. C# allows a class to inherit from multiple classes but only one interface. F
只能繼承一個類，但可以實現多個接口
7. A property declaration must contain both a get accessor and a set accessor. F
可以只包含其中一個
8. Structs can be inherited. F
Struct結構體不支持繼承
9. If the parameter modified by keyword ‘out’ is not initialized within the method, it will be automatically assigned with the default value of its own type. F
out在使用之前會將傳入參數清空，不管其原本是什麼值。必須人爲爲其賦新值。
10. Defining a method with modifier ‘protected’ will only allow this class and its derived class to access it. T
class SomeClass
{
//可以從任何地方訪問
public void PublicMethod()
{
}
//僅可以從SomeClass類型中訪問
private void PrivateMethod()
{
throw new System.NotImplementedException();
}
//可以再SomeClass類和它的派生類中訪問
protected void ProtectMethod()
{
throw new System.NotImplementedException();
}
//可以在同一個程序集中訪問
internal void InternalMethod()
{
throw new System.NotImplementedException();
}
//在程序集中受保護的訪問
protected internal void ProtectInternalMethod()
{
throw new System.NotImplementedException();
}
//沒有標記的成員在C#中默認爲私有的
void SomeMethod()
{
throw new System.NotImplementedException();
}
}程序集：被編譯到同一個dll或exe中的程序就是處於同一個程序集中，在不同的dll或exe文件中的程序就是處於不同的程序集中。
三、填空題
1. Class modified by keyword ___sealed_____ are not allowed to inherit from. 密封類
2. To split(切分) one class definition into multiple files, you use class modifier ____partial_.
一個類被拆分到多個文件中之後，需要在每個文件中使用partial(分部)關鍵字來定義 類的不同部分。
3. Class defined like “class Buffer<Element Type>{...}” is often called ____generic class___. 泛型類
4. If you are to overload operator >=, then operator ___<=____must also be overloaded manually.
==、！=；>、<;>=、<=必須成對重載
5. You use the overloaded operator __+_____to register a compatible method to a delegate variable while not offending those methods already registered.
6. Reform statement ‘b=((a is B)?(B)a:null)’ with keyword ‘as’ ______b=a as B_.
https://www.cnblogs.com/cgli/archive/2011/05/10/2041731.html
7. Assum x and y are ansigned integer type. Please reform expression ‘(x*7-y)/4’ only using left/right shifts and add/subtract operators ____x<<1-x>>2-y>>2___.
乘2左移1位，除2右移1位
8. In array ‘int[] a={1,4,2,5,3}’, what is the value of a[a[a[2]]] ? _____2__.
9. Suppose there is a string array, now we are use Linq to Objects to query it:
string[] valleys={“Greenill”,”WilliNeer”,”Vakumy”,”Alitheir”,”NutteR”};
var Result = from v in valleys where v.EndsWith(“r”) orderby v select v.ToLower();
please orginaze the result into oneline, use spaces to separate items.
____alitheir___ __nutter_____ ____willineer___ _______ _______
ToLower方法把字母字符轉化爲小寫；
10. Here is part of help information of csc.exe below. Please write a command to compile Main.cs with library Utils.lib to generate a console executable Program.exe.
___csc____ ____/r:Utils.lib___ ___/out:Program.exe____ Main.cs_______ _______
四、簡答題
1. What is the difference between the virtual method and the abstract method?
抽象方法是隻有方法名稱，沒有方法體（也就是沒有方法具體實現），子類必須重寫父類抽象方法；
虛函數是該方法有方法體，但是子類可以覆蓋，也可不覆蓋。
（1）虛方法有方法體，抽象方法沒有方法體。抽象方法是一種強制派生類覆蓋的方法，否則派生類將不能被實例化；
（2）抽象方法只能在抽象類中聲明，虛方法不是；
（3）派生類必須重寫抽象類中的抽象方法，虛方法則不必要。
2. Write down the difference between overloading and overriding.
重載某個方法是在同一個類中發生的！重寫是在子類中重寫父類中的方法。
1.override: 父類：public virtual string ToString(){return "a";}
子類：public override string ToString(){return "b";}
2.overload: 同一類中或父子關係類中皆可.
public string ToString(){return "a";}
public string ToString(int id){return id.ToString();}
重寫(override)是用於重寫基類的虛方法,這樣在派生類中提供一個新的方法；
重載(overload)是提供了一種機制, 相同函數名通過不同的返回值類型以及參數來表來區分的機制
3. Give a brief description about the difference and connect between the class and interface.（至少7個）
http://www.jb51.net/article/37971.htm