QBasic/Working With Strings

What are strings and what are they used for? edit

In QBASIC, a string is a contiguous sequence of ASCII encoded characters in memory. The characters are stored in memory as an 8 bit byte. Strings in QBASIC are mutable meaning they can be changed in place without allocating new memory. By now if you have read the prior chapters, you should know that strings are typically used to represent numbers, letters, and other symbols and are used to display information on screen, and getting user input. In the Files chapter you will find that strings can be saved into and read from files as well. If you get creative you can use strings for other purposes. One example is adding large numbers hundreds of digits long. In QBASIC you cannot do that with its built in numeric data types. You could however store the digits in string form and write your own function to add a couple of strings containing digits together thus overcoming some of the initial QBASIC constraints.

Functions edit

Character Functions edit

Asc edit

Chr$ edit

String Functions edit

Conversion edit

Lcase$ edit
Str$ edit
Ucase$ edit

Generator edit

Space$ edit
String$ edit

Search edit

InStr edit

Size Of edit

Len edit

Splice edit

Left$ edit
Mid$ edit
Right$ edit

Truncate edit

Ltrim$ edit
Rtrim$ edit

Memory Manipulation Functions edit

Peek edit

Poke edit

SADD edit

Examples edit