Conditional Statements
Syntax of if condition :
Syntax 1
If (condition)
Statement 1 ;
Else
Statement 2;
Syntax 2
If (condition)
{
Statement 1 ;
Statement 2;
}
Else
{
Statement 3;
Statement 4;
}
Nested If:-
If (condition)
Statement 1 ;
Else If (condition)
Statement 1 ;
Else If (condition)
Statement 1 ;
Else
.
Else
Statement;
Examples on if statment
A program to compare two numbers (I and j), if I is grater change from back color to green otherwise REO.
Open windows forms application project
Place two textboxes and a button Click on button 1
Code for button 1
Int I = int. parse (text Box 1. text);
Int j =int. parse (text Box2.text);
If (i> j)
This. Back color = color. Green;
Else
This. Back color = color. Red;
Execute the project
Observations
What is this key ?
this is a keyword
this works like an object for current class
this will be created at run time.
this is under control of CLR.
Working with Switch condition
Switch syntax
Switch (variable)
{
Case 1:
Statements;
Break;
Case 2:
Statements;
Break;
.
Default
Statements;
Break;
}
Example on Switch condition
Open windows forms application project
Place a text box and a button
Code for button 1 click
{
Int I = int. parse (text box 1. text);
Switch (i)
{
….
}//switched close here
Switch (i)
{
Case 1:
This. back color = color. Green ;
Break;
Case 2 :
Color dialog c = new dialog ();
Creating an object
- show dialog ();
this. Back color = c. color;
break;
case 3:
Application . Exit ();
Break;
Default :
Message box . show (“enter 1,2, or 3 only”);
Break;
}// switch closed here
Execute the project
Observations
Syntax to create an object
Class name (space) obj _name = new class name ();
EX:-
Color dialog is a predefined class
Application is a class which contains Exit () method
Purpose of exit () is to terminate the project