微软认证答案及解析

QUESTION 1

You want to create a transaction, but you do not want anyone to modify the rows in aDataSet

object until the transaction is finished.

What isolation level should you use? (Select the best choice.)

A.

ReadCommitted

B.

ReadUncommitted

Explanation/Reference:

Section: 3. Consuming and Manipulating Data

Choice d is correct. The Serializable value of the TransactionIsolationLevel enumeration specifies

that no users should be able to add rows or modify data in a data set while a transaction is open.

The ReadCommitted value specifies that locks are placed on the data while it is being read, but

data can still be altered before the transaction is complete. No locks are held in

aReadUncommitted transaction. With RepeatableRead, a transaction will prevent others from

modifying data while a transaction is open, but phantom rows can still be created.

Reference:

MSDN, Search, "TransactionIsolationLevel Enumeration," ".NET Framework Class Library."

file will properly store a database name of Finance? (Select the best choice.)

A.

<key="DBName" value="Finance">

B.

<MyApp key="DBName" value="Finance">

C.

<add key="DBName" value="Finance">

D.

Explanation/Reference:

computer. Settings located under the <appSettings> element apply to individual applications on

the computer. In a scenario where an application is stored on a server, no specific application

configuration file resides on each workstation. To add settings specific to an application in

aMachine.config file, the application name must first be added with the <add> element.

Reference:

MSDN, Search, "Machine Configuration Files," ".NET Framework Developer's Guide."

QUESTION 3

An application is reporting syntax errors when the project is compiled.

Which of the following windows should you use to view the errors? (Select the best choice.)

A.

D.

Call Stack

Answer: A

Section: (none)

Explanation/Reference:

Choice a is correct. The Output window displays syntax errors that occur when building an

application. It also provides Debug and Trace output. By right-clicking the error and selectingGo

To Error/Tag, you can navigate to the lines of code that are responsible for the errors. The Locals

MSDN, Search, "Output Window," "Visual Studio."

You have inherited an application from a former colleague. The application contains aMainMenu

component named myMainMenu. Your company wants you to give the application the ability to

display part of the main menu, MenuEditItem, in a popup menu when the user right-clicks a

particular text box. You have added a ContextMenu component, PopupMenu, to the main form.

You want to write the fewest lines of code to create the popup menu.

Which of the following lines of code should you use in your solution? (Select the best choice.)

A.

PopupMenu = MenuEditItem;

C.

Section: (none)

Explanation/Reference:

Choice a is correct. You should use the

PopupMenu.MenuItems.Add(MenuEditItem.CloneMenu());statement to create the popup menu.

The CloneMenu method provides a simple way of creating a popup menu based on an

existingMainMenu object. Assigning the popup menu to the ContextMenu property of a control

will cause the popup menu to appear when the user right-clicks the control. Popup menus cannot

be created by simply setting the ContextMenu object equal to a MainMenu object.

Reference:

QUESTION 5

in your target market do not have a large budget for computer hardware, so most of their

computers are older systems with limited resources.

application? (Select the best choice.)

A.

Override the Finalize method. Within the overridden method, destroy and release all critical

resources. Call the Finalize method just before setting the last of the object's reference variables to

null.

B.

When you are finished with an object reference, explicitly destroy the reference by setting it

tonull.

C.

and release all critical resources. Call this method just before setting the last of the object's

reference variables to null.

Explanation/Reference:

Choice c is correct. To minimize resource requirements for the grade book application, you should

implement the IDisposable interface and, in the IDisposable.Dispose method implementation,

destroy and release all critical resources. You should also call this method just before setting the

last of the object's reference variables to null. The IDisposable interface provides a mechanism

through which scarce resources can be released without waiting for the Garbage Collection

process. The programmer must ensure that the Dispose method is called only when the last

reference to an object is being destroyed.

The Finalize method is declared as protected and cannot be called from any code that is not a part

of a child of the object. Setting the reference to null simply flags the object so that the Garbage

Collector will destroy it and free its resources on its next pass. Forcing Garbage Collection to

"Reference," "Class Library," "System," "IDisposable Interface," "Methods,"

"IDisposable.Dispose Method."

Examine the following code sample:

int I1 = 0;

double D1;

DateTime dte = new DateTime(2002, 4, 1, 0, 0, 0, 0);

try

{

I1 = dte.AddSeconds(-0.75).Day;

}

{

I1 = 1000;

}