-
How to Convert String to Integer without using any BuiltIn Functions ?
Pattiwack
- Nov 2nd, 2011
I tihnk they want to see if you can manually convert the string..."c# int nResult = 0; int nNeg = '-'; int nMin = '0'; int nMax = '9'; bool bNegate = false; for(int i =0; i < sStr...
latapaka
- Oct 14th, 2008
String test = "100"; int test1 = Convert.ToInt32(test); Console.Write(test1); Console.Read();
-
Explain the advantages and limitations of using Aliases in C#?
LordAlex
- Nov 3rd, 2011
C# provides a set of predefined struct types called the simple types. The simple types are identified through reserved words, but these reserved words are simply aliases for predefined struct types in the System namespace.
{sbyte, byte, short, ushort, int, uint, long, ulong, and char}PeterVH
- Aug 19th, 2011
Well, it is needed if for some reason you have conflicting names. Silly example, but suppose you declare a variable with the name DateTime, and to be very funny (sarcasm) you also define a variable na...
-
Can abstract classes have constructors? If the answer is yes, when do they get called?
vaneet
- Jun 3rd, 2008
Yes, the abstract classes can have constructors.But they can be run only by the subclasses of the abstract class
kiran prasad
- Dec 4th, 2007
Yes, Abstract classes have constructors.They are called when their derived class objects are instantiated..For more information, READ : Chapter 4, Professional C# 2005 by Wrox publications...Thanks.
-
C# Error - Overload for method
I took a button in form.I have two classes emp and bonus.bonus class is inherited from emp class.If bonus is giving ie in dialog box if we select ‘Yes’ b ie bonus is added to sal and we get ts ie total sal along with eno.If bonus is not given ie in dialog box if we select ‘No’ we need to get only sal along with eno.The following pgm is working fine.class emp { private int...
bhanu supriya
- Jul 19th, 2010
Here you are passing parameters to the class itself...You have to pass the parameters to method.
sudhakarr.net
- Jul 11th, 2008
Hi aarruunnaa,You try this code, if it is useful for you send me reply otherwise ask me again dont hesitate class emp {public int eno,sal; public emp(){}public emp(int eno,int sal) {this.eno=eno;...
-
Inheritance
What is the importance of inheritance in c# and why i used?
tllprmahesh
- Jan 9th, 2009
Classes are inherit from another class. Basically we are using OOPS for reusability, so inhertiance means deriving new class from base class, it occupies less memory.
nikhilrawat23
- May 27th, 2008
basically the main advantage of object orineted approach is code reusabilty which help us to improve performance by using less memory for computation.inharitance provide us code reusabilty by accessin...
-
What is the use of fixed statement in c#?
asifdcsku
- Sep 12th, 2008
Fixed is used while doing type casting Fixed ensures that no exception will be thrown even if we are doing a wrong cast.
Vikas Yadav
- Apr 2nd, 2008
The fixed keyword is responsible for the pinning of managed objects(maanged by CLR). Pinning is the act of specifying to the GC that the object in question can’t be moved.Permitted in unsafe context only i.e wwhen u are using pointers in C#.
-
Uses of delegates
What is a delegate in C# and when are they commonly used in Windows Forms programming?
hdkhanna
- May 18th, 2010
Delegates are an efficient way of calling methods dynamically in C#. As long as the signature of the method called is the same as the delegate type defined it can be called. This is one way a method c...
asifdcsku
- Sep 12th, 2008
Delegeates are reference to methods Delegates are most commonly used in event handling.
-
Delegates and Generics in c#
What is the advantage of using delegates and Generics in c# .
Read Best Answer
Editorial / Best Answer
sutanu_halder- Member Since Dec-2007 | Apr 18th, 2008
Advantage of Generic:-
1. Generics provide type safety without the overhead of multiple implementations.
Ex. We can create a linked list of string.
LinkedList<string>linkList=new LinkedList<string>();
There is no need to inherit from a base type and override members.The linked list is ready
for immediate use.
2. There is no need to write code to test for the correct data type because it is enforced
at compile time. The need for type casting and the possibility of run-time errors are
reduced.
3. Generic collection types generally perform better for storing and manipulating value
types because there is no need to box the value types.
4. Generic delegates enable type-safe callbacks without the need to create multiple delegate
classes.
5.Generic delegates can also be used in dynamically generated code without requiring the
generation of a delegate type. This increases the number of scenarios in which you can use
lightweight dynamic methods instead of generating entire assemblies.
Advantage of Delegate:
Delegates are managed function pointers. they are type checked and held in spaces that can
be reclaimed by the memory manager.chintan.desai
- Aug 7th, 2009
Adding on sutanu_halder answer: 1. Delegate executes asynchronousely, while Generice execute synchronousely. 2. Delegate is not type safe. We can define anonymous method which can execute without creating delegate object in memory. Generic is type-safe.
sutanu_halder
- Apr 23rd, 2008
Advantage of Generic:-1. Generics provide type safety without the overhead of multiple implementations.Ex. We can create a linked list of string. LinkedList<string>linkList=new...
-
C# Calender Days
How to find out how many calender days are there between two dates in c#.net?
Read Best Answer
Editorial / Best Answer
wyverex- Member Since May-2008 | May 13th, 2008
DateTime t1 = new DateTime(2008, 5, 13);
DateTime t2 = new DateTime(2004, 2, 22);
TimeSpan span = (t1 > t2 ? t1 - t2 : t2 - t1);
Console.WriteLine(span.TotalDays);ngobeseb
- Nov 4th, 2009
Here is the better answer:DateTime fDate = DateTime.Now;int thisDay = fDate.DayOfYear; //if today's date is 31/12/2008, thisDay will be 365 and if today's date is 01/01/2009, thisDay will be 1.Therefore, you can use DayOfYear propery to get the day number in a year.
dhanu_mitra
- Jan 1st, 2009
public void DateDiff(){ DateTime startDate = DateTime.Parse("11/12/2008"); DateTime endDate = DateTime.Parse("11/12/2009"); &n...
-
Unsafe Keyword
Why we use pointer in C#.NET with Unsafe keyword?
phanish
- Jul 16th, 2010
In C# the value can be directly referenced to a variable, so there is no need of pointer. Use of pointer sometime crashes the application. But C# supports pointer, that means we can use pointer in C#....
kvvsmbalaji
- Jul 16th, 2010
As we know, the CLR is responsible for managing the execution of code compiled for the .NET platform. The code that satisfies the CLR at runtime in order to execute is reffered as Managed Code.Un...
-
YIELD Keyword
What is the purpose of YIELD Keyword in C#?
diejmon
- Aug 18th, 2010
The yield keyword is used in an iterator block to provide a value to the enumerator object or to signal the end of the iteration. When used the expression is evaluated and returned as a value to the e...
phanish
- Jul 17th, 2010
Used in an iterator block to provide a value to the enumerator object or to signal the end of iteration. It takes one of the following forms: yield return ;yield break;
-
Singleton Class
Give an example of inbuilt Singleton Class in .NET.
BhavinRudani
- Dec 23rd, 2010
The Singleton is class which only allows a single instance of itself to be created and usually gives access to the instace.Benifits:Instance ControlSingleton class prevents other object from instantia...
sushil_gupta
- Oct 8th, 2010
In Singleton class we can create only one object throughout the lifetime of class.Singleton is a design pattern and based on that pattern this class is implemented.
-
Late and early binding
which one best in late binding and early binding? What is the difference between them ?
Sivavt
- Mar 26th, 2012
Early binding Or Compile time Or static binding: Assigning of object to type reference happens at compile time.
Late binding Or Run time Or Dynamic binding: Assigning of object to type reference happens at run time.
Early binding is efficient while late binding provides flexibility to programmers.Devender Thadkapalli
- Nov 28th, 2011
Early binding is best. Because any errors can be resolved at compile time. Late binding is at Run Time
-
Properties in C#
What are properties in C#? What are the advantages of using Properties ?
Riki
- Sep 1st, 2015
Properties are a level of abstraction to access private fields of a class and they are declare as public. Field are always private member of a class.
-
Can we write Dotnet Console program in Unix
Can we write Dotnet Console program in Unix ? If yes Give one example.
TheDentist
- Apr 23rd, 2013
If you write in Java then the application will run in a JRE on UNIX but you have to compile the application on Windows first. Then deploy it to UNIX.
-
Advantages of static class over class ?
When to use static class and when to use normal class ?
Sunil
- Aug 31st, 2014
WHEN SHOULD WE DO THIS: When we have a normal class and its methods being used very frequently in a given app, then it would speed up things if we made this class a static class with static methods. T...
Knoxille_25
- Aug 19th, 2014
A static class can make your implementation simpler and faster because you do not have to create an object in order to invoke its methods. It is useful to organize the methods inside the class in a meaningful way, such as the methods of the Math class in the System namespace.
-
Why do I get a syntax error when trying to declare a variable called checked?
The word checked is a keyword in C#.
Elean0r
- May 23rd, 2011
checked is a keyword in c#, which causes designated expressions to be checked for arithmetic overflow. It may be used in one of two ways:1) block - checked {} , where the block of statements enclosed ...
Vikas Yadav
- Apr 5th, 2008
Reason is checked is a keyword in C#,but if u want to keyword as an identifier use @ with it.e.g int @checked=3;This works with all the keywords,but it is recommended to avoid it.
-
How do I create a Delegate/MulticastDelegate?
C# requires only a single parameter for delegates: the method address. Unlike other languages, where the programmer must specify an object reference and the method to invoke, C# can infer both pieces of information by just specifying the method's name. For example, let's use System.Threading.ThreadStart: Foo MyFoo = new Foo();ThreadStart del = new ThreadStart(MyFoo.Baz);This means that delegates can...
Read Best Answer
Editorial / Best Answer
Answered by: Raghu
- Sep 29th, 2005
This article is good.
Introduction
In this article I am going to share my knowledge on Delegates in C#.This would explain the Delegate using simple examples so that the beginner can understand the same.What is Delegate?
Definition:
Delegate is type which holds the method(s) reference in an object.
it is also reffered as a type safe function pointers.
Advantages:
.Encapsulating the method's call from caller
.Effective use of Delegat improves the performance of application.
.used to call a method asynchronously.
Declaration:
public delegate type_of_delegate delegate_name()
Example : public delegate int mydelegate(int delvar1,int delvar2)
Note:
.you can use delegeate without parameter or with parameter list
.you should follow the same syntax as in the method
(if you are reffering the method with two int parameters and int return type the delegate which you are declaring should be the same format.This is how it
is reffered as type safe function pointer)
Sample Program using Delegate :
public delegate double Delegate_Prod(int a,int b);
class Class1
{
static double fn_Prodvalues(int val1,int val2)
{
return val1*val2;
}
static void Main(string[] args)
{
//Creating the Delegate Instance
Delegate_Prod delObj = new Delegate_Prod(fn_Prodvalues);
Console.Write("Please Enter Values");
int v1 = Int32.Parse(Console.ReadLine());
int v2 = Int32.Parse(Console.ReadLine());
//use a delegate for processing
double res = delObj(v1,v2);
Console.WriteLine ("Result :"+res);
Console.ReadLine();
}
}
Explanation:
Here I have used a small program which demonstrates the use of delegate.
The delegate "Delegate_Prod" is declared with double return type and which accepts only two integer parameters.
Inside the Class the method named fn_Prodvalues is defined with double return type and two integer parameters.(The delegate and method is having the same signature and parameters type)
Inside the Main method the delegate instance is created and the function name is passed to the
delegate instance as following.
Delegate_Prod delObj = new Delegate_Prod(fn_Prodvalues);
After this we are accepting the two values from the user and passing those values to the delegate as we do using method .
delObj(v1,v2);
Here delegate object encapsulates the method functionalities and return the result as we specified
in the method.Multicast Delegate
What is Multicast Delegate? :
It is a Delegate which holds the reference of more than one methods.
Multicast delegates must contain only methods that return void, else there is a run-time exception.
Simple Program using Multicast Delegate
----------------------------------------
delegate void Delegate_Multicast(int x, int y);
Class Class2
{
static void Method1(int x, int y) {
Console.WriteLine("You r in Method 1");
}
static void Method2(int x, int y) {
Console.WriteLine("You r in Method 2");
}
public static void Main()
{
Delegate_Multicast func = new Delegate_Multicast(Method1);
func += new Delegate_Multicast(Method2);
func(1,2); // Method1 and Method2 are called
func -= new Delegate_Multicast(Method1);
func(2,3); // Only Method2 is called
}
}
Explanation:
In the above example you can see that two methods are defined named method1 and method2 which takes two integer parameters and return type as void.
In the main method the Delegate object is created using the following statement
Delegate_Multicast func = new Delegate_Multicast(Method1);
Then the Delegate is added using the += operator and removed using -= operator.
Naveen Kumar Shivanadri
- Sep 8th, 2016
Delegate is not type. It is just pointer method which is used to improve the performance. Suppose we want to execute a method 10 times by using calling method by using class name or instance, 10 time...
Rajesh Muurya
- Aug 9th, 2016
I have some doubt.
Raghus Says: Delegate is type which holds the method(s) reference in an object.
My question is if Delegate is type then how we create a object of delegate? Because, we know that we can create object only struct and class. -
When you inherit a protected class-level variable, who is it available to?
Classes in the same namespace.
Basavarajayya
- Nov 14th, 2009
Its available only to the derived classes and not all the classes in the NameSpace
anil4kick
- Sep 26th, 2009
Protected level variable is available to only sub classes(i.e class inherited from this base class).
-
What does the keyword virtual mean in the method definition?
The method can be over-ridden.
smandke
- Aug 27th, 2010
Virtual method in C# is a used to support polymorphism. This means that in a base class we will define a method foo1() with the keyword "virtual" and the derived classes will inherit t...
sahajanandk
- Mar 9th, 2009
Keyword virtual is used to make changes to the methods inside the virtual class while runtime. the virtual class should be overide with the same modifier, return type and the name.
C# Interview Questions
Read Best Answer
Ans