Difference between revisions of "Character and string types"
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== WideChar == | == WideChar == | ||
| − | A variable of type '''WideChar''' is exactly 2 bytes in size, and contains one [[LCL Unicode Support|Unicode]] character in UTF-16 encoding. | + | A variable of type '''WideChar''' is exactly 2 bytes in size, and contains one (part of) [[LCL Unicode Support|Unicode]] character in UTF-16 encoding. |
| + | Note: it is impossible to encode all Unicode code points in 2 bytes. Therefore, 2 WideChars may be needed to encode a single code point. | ||
{| class="wikitable" style="text-align:center; width:50px" | {| class="wikitable" style="text-align:center; width:50px" | ||
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==== Reference ==== | ==== Reference ==== | ||
* [http://www.freepascal.org/docs-html/ref/refsu8.html FPC WideChar documentation] | * [http://www.freepascal.org/docs-html/ref/refsu8.html FPC WideChar documentation] | ||
| + | * [https://en.wikipedia.org/wiki/UTF-16] | ||
== PChar == | == PChar == | ||
Revision as of 16:31, 28 December 2013
Free Pascal supports several types of characters and strings.
AnsiChar
A variable of type AnsiChar is exactly 1 byte in size, and contains one ASCII character.
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Reference
WideChar
A variable of type WideChar is exactly 2 bytes in size, and contains one (part of) Unicode character in UTF-16 encoding. Note: it is impossible to encode all Unicode code points in 2 bytes. Therefore, 2 WideChars may be needed to encode a single code point.
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Reference
PChar
A variable of type PChar is basically a pointer to a Char type, but allows additional operations. PChars can be used to access C-style null-terminated strings, e.g. in interaction with certain OS libraries or third-party software.
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Reference
PWideChar
A variable of type PWideChar is a pointer to a WideChar variable.
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Reference
String
The type string may refer to ShortString or AnsiString, depending from the {$H} switch. If the switch is off ({$H-}) then any string declaration will define a ShortString. If it is on ({$H+}) string without length specifier will define an AnsiString, otherwise a ShortString with specified length.
