-
C# Data Table Multiple Rows
You have multiple rows in C# data table and you have to save it in database using just one call, How will you do it?
Read Best Answer
Editorial / Best Answer
LordAlex- Member Since Nov-2011 | Nov 5th, 2011
In a typical multiple-tier implementation, the steps for creating and refreshing a DataSet, and in turn, updating the original data are to: 1. Build and fill each DataTable in a DataSet with data from a data source using a DataAdapter. 2. Change the data in individual DataTable objects by adding, updating, or deleting DataRow objects. 3. Invoke the GetChanges method to create a second DataSet that features only the changes to the data. 4. Call the Update method of the DataAdapter, passing the second DataSet as an argument. 5. Invoke the Merge method to merge the changes from the second DataSet into the first. 6. Invoke the AcceptChanges on the DataSet. Alternatively, invoke RejectChanges to cancel the changes.
Vasu
- Apr 10th, 2015
Yes
indrajith
- Jan 22nd, 2015
We can use SqlBulkCopy class here for example
Code- span style="color: #ff0000;">"dbtablename"
Which operator is used for TypeCasting
A) [ ]B) ( )C) TypeOf
Logan
- Mar 26th, 2015
B
Which of the following statement is invalid with regards to constructor
A) Constructors should have the same name as class nameB) Constructors have to be public so that class can be instantiatedC) Constructors can not be overloadedExplanation: Constructors can be overloaded with different parameters
Which of the following statements is not true for interfaces
A) Interface definitions does not have implementationB) Interfaces must be declared as publicC) Interfaces can be instantiatedD) Interface does not have constructorsExplanation: Interfaces can only be implemented by inheriting and they can not be instantiated
Saurabh
- Dec 24th, 2014
Both B & C are wrong. Interfaces can be private and in that case public classes cannot inherit them. You can define it within a class. C is wrong as we cannot create an instance of the interface.
TheDentist
- Apr 23rd, 2013
C is the correct answer. Interfaces dont have constructors so they cant be instantiated.
http://msdn.microsoft.com/en-US/library/vstudio/ms173156.aspx
In a multilevel hierarchy how are the constructors are called
A) TopDownB) BottomUpC) None
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.
The following code fails. Why?
int a = 5; int b = 5; object oa = a; object ob = b; Debug.Assert(oa == ob, "oa is not equal ob");
chidski
- Oct 17th, 2013
Given code fails bcoz. debug result is wrong.. Please see below int a = 5; int b = 5; object oa = a; object ob = b; Debug.Assert(oa != ob...
When to use string classes
when we have string builder which are mutable why we need immutable string classes in C#.
Denial
- Aug 14th, 2013
String: String are immutable that is every time you make changes to a string object, the string is destroyed and a new string is created with modifications you applied to previous string. All this is ...
Sivavt
- Mar 25th, 2012
String is immutable, meaning, if there is any change in the string value, run time allocates new memory & assign it to the string reference. For the programmer, it looks like the same string but inter...
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.
How to clear screen using c# console application...?like clrscr() in c++..!
Anuj Malik
- Oct 5th, 2012
Console.Clear(); its work absolute in c# "c# using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace ConsoleApplication9 { class stud...
amreenkhader
- Jan 20th, 2012
To clear the screen we can use the clrscr() command followed by ; to clear the input given to the program
Wap on 3d matrix by using random function print o/p in a file.
Wap on 3d matrix by using random function print in a file.
Find the prime numbers from out put of above program.
Find the even numbers from o/p of 1st program.
Find the odd numbers from o/p of 1st program.
Program on 3d matrix using random function print the o/p in file.
program on 3d matrix using random function print the o/p in file
find the even,odd,prime numbers from above output file.
please do needful help
thank youMy switch statement works differently! Why?
C# does not support an explicit fall through for case blocks. The following code is not legal and will not compile in C#: switch(x){case 0:// do somethingcase 1:// do something in common with 0default:// do something in common with//0, 1 and everything elsebreak;}To achieve the same effect in C#, the code must be modified as shown below (notice how the control flows are explicit): class Test{public...
TheOutlander
- Aug 21st, 2010
Most of the other answers are right, but there is a caveat.Empty cases are allowed to fall through. However, the last case statement always needs a break - empty or not.
By declaring a base class function as virtual we allow the function to be overridden in subclasses
A) TrueB) FalseExplanation: If a function is declared virtual it needs to be overridden in subclass
Sivavt
- Mar 29th, 2012
It is not mandatory for a derived class to override the virtual base method. Nevertheless, derived class can opt to override the virtual base method to redefine the functionality.
Dinesh M Yadav
- Aug 28th, 2011
The answer is A) TRUE. If you declare a virtual method in a class , its not mandatory to override it in the sub class. However, In case of abstract class, the answer would be B) False since if you ...
C# sealed variables
I have taken a windows application and a button control in it.I want to declare a variable as a sealed and use that variable with in same class as we cannot use in other class. class test { public sealed int x = 5; public void abc() { MessageBox.Show(x.ToString()); } } class best :test { ...
Sivavt
- Mar 29th, 2012
Keyword sealed can be used with class declaration to prevent it from being sub-classed.
Keyword sealed can be used in method declaration to prevent it from being overridden.
Rajeeva
- Sep 4th, 2011
To restrict users from inheriting the class by sealing the class using "sealed" keyword i.e. no class can be drieved from a sealed class. both Class and Method can be sealed, in that case Method cannot be overridden.Exception Handling
what is the necessary for "throws" and "throw" in exception handling??
Even Though the exception has been thrown automatically and being handled by try and catch block..
Suresh Jayaraman
- Sep 23rd, 2011
if we have different layers like Dataaccess layer,Business layer ,Presentation layer. The error is in DataAccess layer,that error should come to presentation layer and we can show that error in messa...
Read Best Answer
Ans