But in the long run, you better go with the flow. You can fight the Lazarus system and declare your stings as being of a certain codepage and use RawByteString to prevent the compiler form doing unwanted codepage conversion. So "i with accent", which consist of 2 bytes is treated as 2 separate chars, and how they look on the console is dependant on your codepage. It can only display 255 different characters, and it treats strings as being single byte encoded. When you write to the console, you have to understand that the console has a different codepage altogether. UTF8Length(): it returns the length in "UTF-8 characters", instead of the length in bytes (as Length() does): Utf8Length('Ä') is 1, whilst Length('Ä') is 2.ĭisplaying UTF-8 encoded strings will be displayed as expected in any visual component of Lazarus. The LazUTF8 unit from Lazarus has various functions to handle UTF8 encoded strings.Į.g. This makes iteration through a UTF-8 encoded string more complex than old style single byte encoding (ALIAS codepages). In UTF-8 all plain ASCII (so up to #127) are stored as a single byte.Īll other "characters" are stored as 2, 3 or 4 byte sequences. So, the string contains more bytes than "characters", since the "lowercase i with accent" is made up of 2 bytes. The type String in Lazarus is by default also UTF-8. The Lazarus IDE stores everything in UTF-8 encoding. In a COM context they are governed by the COM marshaling subsystem if available. Note that BWSTR types rely on COM marshaling or - when used alone - copy semantics instead of reference counting. UnicodeString is similar to WideString but UnicodeString is a managed type and has a reference count whereas widestring is a BWSTR compatible stringtype that is COM compatible and is not reference counted.It is a BWSTR compatible string type and has no reference count. WideString has a variable length like AnsiString but contains WideChar instead of Char.RawByteString is an alias for AnsiString.AnsiString has a variable length that is limited only by the value of High(SizeInt) (which is platfom dependant) and available memory.If a ShortString length is not explicitly given, then the length is implicitly set to 255. name : String ) but is limited to 255 characters. ShortString has a fixed maximum length that is decided by the programmer (e.g.
The different string types - ShortString, AnsiString, WideString and UnicodeString - differ with respect to length and content: Note that all types of longstring are managed types, whereas ShortStrings are not managed types: they have no reference count. If compiler directive // String is an alias for AnsiString var name : String // name is a ShortString variable since a length specification overrides the alias setting String is an alias for ShortString, AnsiString or Unicodestring (UTF16) depending on a compiler setting. StrA := Age=27 Name=Neil Occupation=Programmerĭelphi Programming © Neil Moffatt All rights reserved.Var s, str1, str2, str3, str4 : string c : char n : integer str1 := 'abc' // assignment str2 := '123' // string containing chars 1, 2 and 3 str3 := #10#13 // cr lf str4 := 'this is a '' quoted '' string' // use of quotes within a string s := str1 + str2 // concatenation c := s // use as index in array n := Length ( s ) // length of string s Alias StrA := 'Age=47 Name=Neil Occupation=Programmer' Be careful doing this in one go - it makes the process more error prone! The second example illustrates this parsing in one run of split. Or the original string can be parsed in one go by providing both the ' ' and '=' characters in the character array parameter. The number of substrings can be limited by the Count parameter.Ĭan be parsed first using ' ' as the separator character to give :Īnd then each of these can be parsed using the '=' separator character. It scans for separating characters, extracting the text either side of the separator into substrings. The Split method is intended to work as a simple string parser. ( CharArray:Array of Char CharArray : Array of Char Count : Integer ) : Array of String ĬF : Methods with this mark are Compact Framework Compatible ( CharArray : Array of Char ) : Array of String Parses a string into an array of substrings
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