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String Variables

So far, the only kind of variables we have used are for holding number values. There are special variables for holding words and other non-numeric character combinations. These variables are called string variables (they hold strings of characters*).

*Characters are:

Letters of the alphabet ;

Digits 0123456789 ;

Any other special symbols like: , . < > / ? ; : ' " [ ] { } ` ~ ! @ # $ % ^ & * ( ) + - \ | etc . . .

Let's look at a very simple program using strings:

input "Please type your name ?"; name$

print "It's nice to meet you, "; name$

This two-line program asks you for your name. Once you've typed it and pressed [Enter], it responds with:

It's nice to meet you, your-name-here

Notice one special thing about our string variable name. It ends with a $ (dollar sign). In BASIC, when you want to store characters in a variable, you end the variable name with a $. This makes it a string variable. As you can see from our program example, you can both input and print with string variables, as we did earlier with our non-string or numeric variables.

We've actually been using strings all along, even before this section about string variables. Whenever you saw a BASIC program line with words in quotes (for example: print "It's nice to meet you, ") you were looking at what is called a string literal. This is a way to directly express a string in a BASIC program, exactly the way we type numbers directly in, only with characters instead. A string literal always starts with a quotation mark and always ends with a quotation mark. No quotation marks are allowed in between the starting and ending quotation marks (point: string literals cannot contain quotation marks).

NOTE - A string can have zero characters. Such a string is often called an empty string. In BASIC, an empty string can be expressed in a string literal as two quotation marks without any characters between them. For example (noCharactersHere$ is the name of our string variable):

let noCharactersHere$ = ""

Next Section: Some things to do with Strings