this keyword in C#

• It works like an object for the current class.
• The this keyword refers to the current instance of the class. 
• When instance variables and local variables are same then this keyword is used to access instance variables.
• In general, local variables overrides instance variables and instance variables are no more visible inside the method. So this can be used to refer instance variables to make visible inside method.
• The this keyword can be used to access members from within constructors, instance methods, and instance accessors.
• For example,

• public class Emp
          {
              private int _Sal = 5000;
              public void increment(int _Sal)
              {
                  MessageBox.Show("Local variable value");
                  MessageBox.Show(_Sal.ToString());//_Sal=3000
                  MessageBox.Show("Instance variable value");
                  MessageBox.Show(this._Sal.ToString());//this._Sal=5000
                  this._Sal = this._Sal + _Sal;
              }//increment
              public void print()
              {
                  MessageBox.Show("Incremented Salary"); 
                  MessageBox.Show(_Sal.ToString());
              }//print
          }//Emp
          private void button1_Click(object sender, EventArgs e)
          {
              Emp em = new Emp();
              em.increment(3000);
              em.print();
          }
      }