Input / Output |
All computer programs have some way to give and/or receive information from the user. When you type a paper in a word processor or enter numbers in a spreadsheet, you are giving the program information.
When you go to a website using a program called a web browser, the data and information is the text and images of the webpage.
Output is when a program gives the user data or information.
Input is when a program receives data or information from the user.
In JUDO, you give the user output by using the following functions:
print()
printLine()
To receive input from the user, use these functions:
readString()
readInt()
readDouble()
readBoolean()
readColor()
Here is an example programs using some of the above functions:
void main() {
String name;
int age;
printLine("Type your name and press enter");
name = readString();
printLine("Hello " + name + ". Now enter your age");
age = readInt();
printLine(name + " you are " + age + " years old");
}
readString()
is used to assign a String value to a String variable.
readInt()
is used to assign an int value to an int variable.
printLine()
prints the value or variable you put between the parenthesis and goes onto a new line
print()
prints the value or variable you put between the parenthesis and does not go onto a new line.
In the program above, you can see that Strings can be joined with String variables or other types of variables to make a longer string by using a plus sign (+). This is useful when you want to print something out to the user that includes the value of a variable.
Making a graphics program like you have already seen how to do is another example of a program that does output. The output is the shapes and colors that you display to the user.
You can view the Input/Output functions in the JUDO Functions Reference.