Editing Letter case (section)

===Methods in programming===
In some forms of [[BASIC]] there are two methods for case conversion:

<syntaxhighlight lang="qbasic">
UpperA$ = UCASE$("a")
LowerA$ = LCASE$("A")
</syntaxhighlight>

[[C (programming language)|C]] and [[C++]], as well as any C-like language that conforms to its [[C standard library|standard library]], provide these functions in the file [[ctype.h]]:

<syntaxhighlight lang="c">
char upperA = toupper('a');
char lowerA = tolower('A');
</syntaxhighlight>

Case conversion is different with different [[character sets]]. In [[ASCII]] or [[EBCDIC]], case can be converted in the following way, in C:
<syntaxhighlight lang="c">
int toupper(int c) { return islower(c) ? c – 'a' + 'A' : c; }
int tolower(int c) { return isupper(c) ? c – 'A' + 'a' : c; }
</syntaxhighlight>
This only works because the letters of upper and lower cases are spaced out equally. In ASCII they are consecutive, whereas with EBCDIC they are not; nonetheless the upper-case letters are arranged in the same pattern and with the same gaps as are the lower-case letters, so the technique still works.

Some computer programming languages offer facilities for converting text to a form in which all words are capitalised. [[Visual Basic]] calls this "proper case"; [[Python (programming language)|Python]] calls it "title case". This differs from usual [[Capitalization#Title case|title casing]] conventions, such as the English convention in which minor words are not capitalised.