this.

Julin James

11y1.5kLearn iOS Programming

''this." what is this command used for?

8 Replies

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Munesh Sharma11y ago
It indicates the current instance. for example you go on following link

http://www.dotnetperls.com/this
Nilesh Jadav11y ago
hey Julian !

The keyword "this" in C# is used to access the field variables. All the field variables must be accessed using "this" keyword.

It is useful when the field variable and the local variables of a method have same name. In the above case local variables overrides field variables and field variables are no more visible inside the method. So this can be used to refer field variables to make visible inside method.
```
class Demo

{

 int a=2,b=10;

 public void Get()

 {

  int a=23,b=34;

  Console.WriteLine("a={0} b={1}",this.a,this.b);

  Console.WriteLine("It is the class variable");

  Console.WriteLine("Now the local variables are:");

  Console.WriteLine("a={0} b={1}",a,b);

 }

}

class MainClass

{

 static void Main(string args[])

 {

  Demo d= new Demo();

  d.Get();

 }

}
```
output:

a=2 b=10
It is the class variable
Now the local variables are:
a=23 b=34

When we write this.a and this.b, it will refer to the field variables. But when we write only a and b it refers to the local variables of the method Get().

As the field variable and local variables have the same name we have to use the this keyword. We can't access a field variable without this keyword in C#. this always refer to the members of same class.

Hope this works !

Upendra Pratap Shahi11y ago

The "this" keyword refers to the class which you are currently writing code in it. I mainly use it to distinct between method parameters and class fields.

For example, let's assume you have the following class:

Hide Copy Code

public class Person {    string name = ""; //Field "name" in class Person        //Constructor of the Person class, takes the name of the Person    //as argument    public Person (string name)    {        //Assign the value of the constructor argument "name" to the field "name"        this.name = name;         //If you'd miss out the "this" here (name = name;) you would just assign the        //constructor argument to itself and the field "name" of the        //Person class would keep its value "".    } }

Depending on where you r using it ,it has different meanings:-
1.Reference to current instance of class
2.Call another constructor from a constructor in same class.
3.Declare indexer
Below example covers above 3

Hide Copy Code

class abc { string x; //class member public abc(string x) { //referring to current instance this.x=x;//("this.x" refers to class member) } //calling another constructor public abc():this("xyz")//calls abc(string x) before abc() { } //declaring an indexer public int this[int index] { get{return x[index];} set{x[index]=value;} }

4.also used in Extension methods

Rajeesh Menoth11y ago
Hi,

It is a reference to the current object.
There are several usages of this keyword in C#.
To qualify members hidden by similar name
To have an object pass itself as a parameter to other methods
To have an object return itself from a method
To declare indexers
To declare extension methods
To pass parameters between constructors
To internally reassign value type (struct) value.
To invoke an extension method on the current instance
To cast itself to another type
To chain constructors defined in the same class
More Details : http://stackoverflow.com/questions/23250/when-do-you-use-the-this-keyword
Bhushan Bhasme11y ago
when You Are calling any method usng object of class then this pointer gets automatically passed.so you can access the datamember of class using this keyword..
Pankaj Kumar Choudhary11y ago
this is a type of pointer that hold the reference of current object of the class
Debendra Dash11y ago
this keyword always point to a current object of a class.
Marc11y ago
"this" is used to assign attributes to an object. Normally when your inheriting from a base object this is used as the attributes from that base model, which in turn can be overridden.

For more details look here..

https://msdn.microsoft.com/en-us/library/dk1507sz.aspx