ASP. NET interview questions (2)

(To original address http://blog.sina.com.cn/s/blog_524c848901009e7b.html ~ Type = v5_one & label = rela_nextarticle author

Li Yang's blog http://blog.sina.com.cn/liiyang)

66. How many stages are there in the software development process? What is the role of each stage?
Answer: demand analysis, architecture design,CodeWriting, QA, and deployment

67. What are the meanings of using and new keywords in C? Using command and statement new create instance new hide methods in the base class.
A: Using introduces namespaces or uses unmanaged resources.
New create an instance or hide the parent class Method

68. to process a string, remove the spaces at the beginning and end of the string. If there are consecutive spaces in the string, only one space is reserved, that is, multiple spaces are allowed in the string, however, the number of consecutive spaces cannot exceed one.
A: String inputstr = "xx ";
Inputstr = RegEx. Replace (inputstr. Trim (),"*","");

69. What is the output of the following code? Why?
Int I = 5;
Int J = 5;
If (object. referenceequals (I, j ))
Console. writeline ("Equal ");
Else
Console. writeline ("not equal ");
A: They are not equal because they compare objects.

70. What is SQL injection and how to prevent it? For example.
A: attackers use SQL keywords to attack websites. Filter keywords, etc.

71. What is reflection?
A: dynamic retrievalProgramSet Information

72. How to Write Design Patterns with Singleton
A: In the static property, the new constructor is private.

73. What is application pool?
A: Web applications, similar to thread pools, improve concurrency performance.

74. What is a virtual function? What is an abstract function?
A: virtual functions: functions that are not implemented can be inherited and overwritten by sub-classes. Abstract function: Specifies a function that must be implemented by a non-virtual subclass and must be overwritten.

75. What is XML?
A: The markup language can be expanded using XML. Extensible Markup Language. Tag refers to the information symbols that computers can understand. With this tag, computers can process various types of information.Article. To define these tags, you can select an international markup language, such as HTML, or use a markup language that is freely determined by people like XML. This is the scalability of the language. XML is simplified and modified from SGML. It mainly uses XML, XSL, and XPath.

76. What is Web service? UDDI?
A: Web Service is a network-based, distributed modular component that executes specific tasks and complies with specific technical specifications. These specifications Enable Web service to interoperate with other compatible components.
The purpose of UDDI is to establish standards for e-commerce. UDDI is a set of web-based, distributed, and standard standards for implementing information registration centers for Web Services, it also contains a set of access protocols that enable enterprises to register their own web services so that other enterprises can discover.

77. What is a user control in Asp.net?
A: The user control is generally used when the content is mostly static, or a little changes... it is relatively large... similar to include... in ASP, but the function is much more powerful.

78. List the XML technologies you know and their applications.
A: XML is used for configuration. It is used to save static data types. Web Services... And config are the most exposed to XML.

What are common objects in 79.ado.net? Describe them separately.
Answer: Connection database connection object
Command database commands
Datareader data reader
Dataset

80. What is code-behind technology.
Answer: aspx, resx, and CS files are separated by code. HTML code and server code are separated to facilitate code compilation and arrangement.

81. What is soap and what applications are there.
A: Simple Object Access protocal. Simple objects accept the protocol. it uses XML as the basic encoding structure and is built on existing communication protocols (for example, HTTP, But Ms is said to be engaged in soap with the underlying architecture on TCP/IP) A protocol that standardizes the use of web services ..

82. C # What are the differences between property and attribute? What are the advantages of this mechanism?
A: attributes are used to access fields of a class, and features are used to identify additional properties of a class or method.

83. Main differences between XML and HTML
Answer: 1. XML is case-sensitive and HTML is not.
2. In HTML, if the context clearly shows where the paragraph or list key ends, you can omit
Or an end tag. In XML, the end mark cannot be omitted.
3. In XML, an element with a single tag but no matching ending tag must end with one/character. In this way, the analyzer does not need to find the end mark.
4. in XML, attribute values must be placed in quotation marks. Quotation marks are usable in HTML.
5. In HTML, You can have attribute names without values. In XML, all attributes must have corresponding values.

What is the ternary operator in 84. C?
A :? :.

85. When integer a is assigned to an object, integer A will be?
Answer: packing.

86. Which of the following types of Class Members are accessible?
A: This.; new class (). method;

87. Public static const int A = 1; is there an error in this code? What is it?
A: The const cannot be modified using static.

88. Float F =-123.567f; int I = (INT) F; what is the I value now _____?
A:-123.

89. What is the keyword of the delegate statement ______?
A: Delegate.

90. What are the characteristics of classes modified with sealed?
A: It is sealed and cannot be inherited.

91. All Custom User Controls in Asp.net must inherit from ________?
A: control.

92. In. net, all serializable classes are marked _____?
A: [serializable]

93. In. Net hosting code, we don't have to worry about memory vulnerabilities. This is because ______?
A: GC.

94. Are there any errors in the following code? _______
Using system;
Class
{
Public Virtual void F (){
Console. writeline ("a.f ");
}
}
Abstract class B:
{
Public abstract override void F (); A: Abstract override cannot be modified together.
} // New public abstract void F ();

95. when class t only declares the constructor of a private instance, ___ can ___ (can or cannot) derive a new class from T outside the program text of T, it is not allowed to create any instance of t directly (either or not.
A: No. No.

96. Is there an error in the following code?
Switch (I ){
Case (): A: // The case () condition cannot be blank.
Casezero ();
Break;
Case 1:
Caseone ();
Break;
Case 2:
Dufault; A: // wrong. The format is incorrect.
Casetwo ();
Break;
}

97. Can system. Web. UI. Page be inherited in. Net?
A: Yes.

What is the error handling mechanism of 98..net?
A: the. NET error handling mechanism adopts the try-> catch-> finally structure. When an error occurs, it is thrown layer by layer until a matched catch is found.

99. The operator statement is used and only = is declared. Is there any error?
A: Do you want to modify equale and gethash () at the same time ()? If "=" is reloaded, it must be reloaded "! ="

100. How to customize messages in. Net (C # Or VB.net) and process these messages in the form.
A: Reload the defwndproc function in form to process messages:
Protected override void defwndproc (Ref system. winforms. Message m)
{
Switch (M. msg)
{
Case wm_lbutton:
/// The format function of string and cstring in MFC is used differently.
String message = string. Format ("Message received! Parameter: {0}, {1} ", M. wparam, M. lparam );
MessageBox. Show (Message); // display a message box
Break;
Case User:
Processed code
Default:
Base. defwndproc (ref m); // call the base class function to process non-custom messages.
Break;
}
}

101. How to disable a form in. Net (C # Or VB.net.
A: Private void form1_closing (Object sender, system. componentmodel. canceleventargs E)
{
E. Cancel = true;
}

102. In. Net (C # Or VB.net), what are the differences between appplication. Exit and form. Close?
A: one is to exit the entire application, and the other is to close one of the forms.

103. There is a double type variable in C #, such as 10321.5, such as 122235401.21644, how to output the value as a currency according to the habits of different countries. For example, in the United States, $10,321.50 and $122,235,401.22 are used, while in the United Kingdom, the ratio 10 321.50 and the ratio 122 235 401.22
A: system. Globalization. cultureinfo myculture = new system. Globalization. cultureinfo ("En-us ");
// System. Globalization. cultureinfo myculture = new system. Globalization. cultureinfo ("En-GB"); the type of the British currency
Decimal y = 9999999999999999999999999999 m;
String STR = string. Format (myculture, "My amount = {0: c}", y );

104. A password only uses five letters (K, L, M, N, and O). The words in the password are arranged from left to right. The password words must follow the following rules:
(1) the minimum length of a password word is two letters, which can be the same or different.
(2) K cannot be the first letter of a word.
(3) If l appears, more than once
(4) M cannot make the last or second-to-last letter
(5) If K appears, N must appear.
(6) If O is the last letter, l must appear
Question 1: Which of the following letters can be placed behind o in Lo to form a three-letter password word?
A) k B) L C) m d) N
Answer: B

Question 2: If the letters K, L, and m can be obtained, what is the total number of two letter-length password words?
A) 1 B) 3 C) 6 d) 9
Answer:

Question 3: Which of the following is the word password?
A) klln B) loml c) mllo d) nmko
Answer: c

8. 62-63 = 1 the equation is not true. Please move a number (do not move the minus sign or equal sign) so that the equation is true. How do you move it?
Answer: 62 is moved to the power 6 of 2.

105. For such an enumeration type:
Enum color: byte
{
Red,
Green,
Blue,
Orange
}
A: String [] Ss = enum. getnames (typeof (color ));
Byte [] BB = enum. getvalues (typeof (color ));

In 106. C #, what are the differences between property and attribute? What are the advantages of this mechanism?
A: attribute: The base class of the custom attribute. property: the attribute in the class.

107. C # Can I perform direct operations on the memory?
A: In.. net ,. net references the garbage collection (GC) function, which replaces programmers. However, in C #, the Finalize method cannot be directly implemented, but the finalize () method of the base class is called in the destructor.

108. Ado. What are the main improvements to net over ado?
A: 1. ado.net does not rely on the ole db provider, but uses it.. Net-managed programs. 2: Do not use com3: do not support dynamic cursors and server-side games. 4: You can disconnect the connection and retain the current dataset. 5: strong type conversion. 6: XML support.

109. Write an HTML page to implement the following functions: "Hello" is displayed when you click the page with the left-click button, and "disabled right-click" is displayed when you right-click the page ". The page is automatically closed in 2 minutes.
A:

110. Briefly describe ASP. NET Server Control Lifecycle
Answer: Initialize loading view status processing sending and returning data loading sending and returning change notification processing sending and returning event pre-rendering save status rendering processing and uninstalling

111. Can anonymous inner class (anonymous internal class) be extends (inherited) other classes, or implements (implemented) interface (Interface )?
A: No. The interface can be implemented.

112. Differences between static nested class and inner class: the more you say, the better.
A: static nested class is an internal class declared as static. It can be instantiated without relying on external class instances. In general, internal classes must be instantiated before they can be instantiated.

113., & and.
& Is a bitwise operator that represents bitwise and operation, & is a logical operator that represents logic and (and ).

114. Differences between hashmap and hashtable.
A: hashmap is a lightweight Implementation of hashtable (non-thread-safe implementation). They have completed the map interface. The main difference is that hashmap allows null key values ), because of non-thread security, the efficiency may be higher than that of hashtable.

115. Short S1 = 1; S1 = S1 + 1; what is the error? Short S1 = 1; S1 + = 1; what is the error?
Answer: Short S1 = 1; S1 = S1 + 1; (the S1 + 1 operation results in int type, which requires forced conversion)
Short S1 = 1; S1 + = 1; (it can be compiled correctly)

116. Can the overloaded method change the type of the returned value?
A: The overloaded method can change the type of the returned value.

117. What is the difference between error and exception?
A: Error indicates that the restoration is not an impossible but difficult case. For example, memory overflow. It is impossible to expect the program to handle such a situation.
Exception indicates a design or implementation problem. That is to say, it indicates that if the program runs normally, it will never happen.

118. What are the differences between <% # %> and <%>?
A: <% # %> indicates the bound data source.
<%> Is a server-side code block.

119. What is the biggest difference between ASP. NET 2.0 (vs2005) and the development tool you used earlier (. NET 1.0 or other? Which development ideas (pattern/architecture) you used on previous platforms can be transplanted to ASP. NET 2.0 (or are already embedded in ASP. NET 2.0)
Answer: 1 ASP. NET 2.0 encapsulates and packages some code, so it reduces a lot of code compared to the same function of 1.0.
2. Both the code separation and page embedding server-side code modes are supported. In the previous version 1.0 ,.. Net prompt help is only available in separated code files. You cannot embed server-side code on the page to get help tips,
3. When switching code and design interfaces, 2.0 supports cursor positioning.
4. When binding data, you can perform operations such as paging, update, and delete on tables in a visualized manner, facilitating beginners.
5. More than 40 new controls are added to ASP. NET, reducing the workload.

120. What is the difference between heavy load and coverage?
Answer: 1. The method overwrites the relationship between the Child class and the parent class. The method overload is the relationship between the methods in the same class and the horizontal relationship.
2. Override can only be composed of one method, or can only be composed of one method. Method Overloading is the relationship between multiple methods.
3. The overwrite request parameter list is the same; the reload request parameter list is different.
4. In the override relationship, the method body called is determined based on the object type (the object corresponds to the bucket type, the method body is selected based on the real parameter table and the form parameter table during the call.

121. To describe the implementation process of the indexer in C #, can I index data only by numbers?
A: No. Any type can be used.

122. in C #, use text or images to describe the differences between string STR = NULL and string STR =.
A: NULL has no space reference;
"" Is a string with a space of 0;

123. Analyze the following code to complete the Blanks
String strtmp = "abcdefg ";
Int I = system. Text. encoding. Default. getbytes (strtmp). length;
Int J = strtmp. length;
After the above code is executed, I = J =
Answer: I = 13.j= 10

124. in the sqlserver server, the given table Table1 contains two field IDs and lastupdatedate. ID indicates the updated transaction number, and lastupdatedate indicates the server time when the update is performed, use an SQL statement to obtain the last updated transaction number.
A: Select ID from Table1 where lastupdatedate = (select max (lastupdatedate) from Table1)

125. Analyze the following code.
Public static void test (string connectstring)

{

System. Data. oledb. oledbconnection conn = new system. Data. oledb. oledbconnection ();
Conn. connectionstring = connectstring;
Try

{
Conn. open ();
.......
}
Catch (exception ex)
{
MessageBox. Show (ex. tostring ());
}
Finally
{

If (! Conn. state. Equals (connectionstate. Closed ))
Conn. Close ();
}
}
Excuse me

1) Can the above Code correctly use the connection pool?

Answer: If the input connectionstring is the same, you can use the connection pool correctly. But exactly the same means that the numbers of spaces in the hyphen are in the same order.

2) can all exceptions in the test method be captured and displayed in the exception handling method used by the above Code?

A: You can only catch exceptions in database connections. (In finally, catch, if there are other operations that may cause exceptions, try and catch should also be used. So theoretically not all exceptions will be caught .)

126. the company requires the development of an inherited system. windows. forms. listview components require the following special features: When you click the headers of columns in the listview, all rows in the view can be rearranged based on the values of each row in the click column (the sorting method is similar to that in the DataGrid ). Based on your knowledge, please briefly discuss your ideas:
A: Based on the column header clicked, the ID of this column is taken out, sorted by the ID, and bound to the listview

127. What is WSE? What is the latest version?
A: The WSE (Web Service Extension) package provides the latest web service security assurance. The latest version is 2.0.

128. In the following example
Using system;
Class
{
Public (){
Printfields ();
}
Public Virtual void printfields (){}
}
Class B:
{
Int x = 1;
Int y;
Public B (){
Y =-1;
}
Public override void printfields (){
Console. writeline ("x = {0}, y = {1}", x, y );
}
What is the output when new B () is used to create B's instance?
Answer: x = 1, y = 0

129. In the following example

Using system;
Class
{
Public static int X;
Static (){
X = B .y + 1;
}
}
Class B
{
Public static int y = a.x + 1;
Static B (){}
Static void main (){
Console. writeline ("x = {0}, y = {1}", a.x, B .y );
}
}
What is the output result?
Answer: x = 1, y = 2

130. What is the difference between abstract class and interface?
A: the class that declares the existence of a method instead of implementing it is called abstract class. It is used to create a class that reflects some basic behaviors, and declare methods for this class, but this class cannot be implemented in this class. You cannot create an abstract instance. However, you can create a variable whose type is an abstract class and point it to an instance of a specific subclass. Abstract constructors or abstract static methods are not allowed. The subclasses of abstract classes provide implementation for all abstract methods in their parent classes. Otherwise, they are also abstract classes. Instead, implement this method in the subclass. Other classes that know their behavior can implement these methods in the class.
an interface is a variant of an abstract class. All methods in the interface are abstract. Multi-inheritance can be achieved by implementing such an interface. All methods in the interface are abstract, and none of them have a program body. The interface can only define static final member variables. The implementation of an interface is similar to that of a subclass, except that the implementation class cannot inherit behaviors from the interface definition. When a class implements a special interface, it defines (to be given by the program body) all the methods of this interface. Then, it can call the interface method on any object that implements the interface class. Because there is an abstract class, it allows the interface name as the type of the referenced variable. Normally, dynamic Association editing will take effect. The reference can be converted to the interface type or from the interface type. The instanceof operator can be used to determine whether the class of an object implements the interface.