if Statement
In this chapter you will learn:
if statement syntax
You can selectively execute part of a program through the if statement. Its simplest form is shown here:
if(condition) {
statement;
}
condition is a Boolean (that is, true or false) expression.
If condition is true, then the statement is executed.
If condition is false, then the statement is bypassed.
The complete form of the if statement is
if(condition) {
statement;
}else {
statement;
}
The general form of the if using blocks of statements is
if(condition)//from j a v a 2 s . com
{
statement sequence
}
else
{
statement sequence
}
if-else-if ladder. It looks like this:
if(condition)/* j av a 2s . com*/
statement;
else if(condition)
statement;
else if(condition)
statement;
.
.
.
else
statement;
Relational operators that can be used in a conditional expression.
else branch
if statement can have an else branch.
The following code prints out There is the value is less than 0.
using System;//ja v a 2s.c o m
class Program
{
static void Main(string[] args)
{
int i = -1;
if (i > 0)
{
Console.WriteLine("Here");
}
else
{
Console.WriteLine("There");
}
}
}
The output:
Nested if statement
You can nest if statements as follows:
using System;//from ja v a2 s.c om
class Program
{
static void Main(string[] args)
{
int i = 5;
if (i > 0)
{
Console.WriteLine("more than 0");
if (i > 3)
{
Console.WriteLine("more than 3");
}
else
{
Console.WriteLine("less than 3");
}
}
}
}
The output:
if statement without braces
If if statement only has one statement we can omit the braces{}.
using System;//from ja v a 2s .c o m
class Program
{
static void Main(string[] args)
{
int i = 5;
if (i > 0)
Console.WriteLine("more than 0");
}
}
The output:
The good practice is to add the braces all the time.
Next chapter...
What you will learn in the next chapter:
- Get to know while loop syntax
- Use a while loop to calculate and display the Fibonacci numbers less than 50