Welcome to Computer Programming

Conditional Statements - if-then-else

In all language (like English) conditional statements are integral to functionality. If a condition is met then do something. We also have if else statements where if something happens, do something, else do something else.

A condition could be if something is

• true
  • if (lightOn)
• == this is for equals - DO NOT USE ONE EQUALS
• >=
• <=
• >
• <
• != this means not equals

if (condition is met)
{
    //do this
}

else  //we do not have to have an else statement)
{
	//do this
}

int k = 250;
if (k==200)
{
	display k is 200
}

else
{
	display k is not 200
}

And and Or

• To use and we use the symbols: &&
• To use or we use the symbol || (which you will find above the enter key)

for example if we wanted two conditions to be met:

if (x>0 && x<25)
{
	do this
}

We can bring multiple statements together

if ((x>0 && x<=5) || x>25)
{
   do this
}

Strings

Strings are objects which makes == generally not work. To check equality for Strings you will use the equals method.

So if you wanted to say

job=="worker"

it should be:

job.equals("worker")

So could block might look like:

if (job.equals("worker"))
    payRate=6;

Else if statements

you can have multiple if statements together-

if (inputString.equals("cat"))
{
	do this
}

else if (inputString.equals("dog"))
{
	do this
}

else if (inputString.equals("fish"))
{
	do this
}

else
{
	//sorry i dont understand your pet
}

If you only have one command for your if statement, you do not need brackets. The if statement will do the following command.

ie:

 if (x>25 && x<50)
    myTool="rectangle";