[Lazarus] TDBEdit, TStringField Size, DataSize, DisplayWidth and MaxLength

[Tony Whyman]

On 11/10/16 15:14, Martin Schreiber via Lazarus wrote:
> MSEgui uses below code in order to guess the Firebird character size:
> "
FYI, this is the table IBX uses to look up character sets and code pages:

   CharSetMap: array [0..69] of TCharsetMap = (
   (CharsetID: 0; CharSetName: 'NONE'; CharSetWidth: 1; CodePage: CP_NONE),
   (CharsetID: 1; CharSetName: 'OCTETS'; CharSetWidth: 1; CodePage: 
CP_NONE),
   (CharsetID: 2; CharSetName: 'ASCII'; CharSetWidth: 1; CodePage: 
CP_ASCII),
   (CharsetID: 3; CharSetName: 'UNICODE_FSS'; CharSetWidth: 3; CodePage: 
CP_UTF8),
   (CharsetID: 4; CharSetName: 'UTF8'; CharSetWidth: 4; CodePage: CP_UTF8),
   (CharsetID: 5; CharSetName: 'SJIS_0208'; CharSetWidth: 2; CodePage: 
20932),
   (CharsetID: 6; CharSetName: 'EUCJ_0208'; CharSetWidth: 2; CodePage: 
20932),
   (CharsetID: 7; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 8; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 9; CharSetName: 'DOS737'; CharSetWidth: 1; CodePage: 737),
   (CharsetID: 10; CharSetName: 'DOS437'; CharSetWidth: 1; CodePage: 437),
   (CharsetID: 11; CharSetName: 'DOS850'; CharSetWidth: 1; CodePage: 850),
   (CharsetID: 12; CharSetName: 'DOS865'; CharSetWidth: 1; CodePage: 865),
   (CharsetID: 13; CharSetName: 'DOS860'; CharSetWidth: 1; CodePage: 860),
   (CharsetID: 14; CharSetName: 'DOS863'; CharSetWidth: 1; CodePage: 863),
   (CharsetID: 15; CharSetName: 'DOS775'; CharSetWidth: 1; CodePage: 775),
   (CharsetID: 16; CharSetName: 'DOS858'; CharSetWidth: 1; CodePage: 858),
   (CharsetID: 17; CharSetName: 'DOS862'; CharSetWidth: 1; CodePage: 862),
   (CharsetID: 18; CharSetName: 'DOS864'; CharSetWidth: 1; CodePage: 864),
   (CharsetID: 19; CharSetName: 'NEXT'; CharSetWidth: 1; CodePage: CP_NONE),
   (CharsetID: 20; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 21; CharSetName: 'ISO8859_1'; CharSetWidth: 1; CodePage: 
28591),
   (CharsetID: 22; CharSetName: 'ISO8859_2'; CharSetWidth: 1; CodePage: 
28592),
   (CharsetID: 23; CharSetName: 'ISO8859_3'; CharSetWidth: 1; CodePage: 
28593),
   (CharsetID: 24; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 25; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 26; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 27; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 28; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 29; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 30; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 31; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 32; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 33; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 34; CharSetName: 'ISO8859_4'; CharSetWidth: 1; CodePage: 
28594),
   (CharsetID: 35; CharSetName: 'ISO8859_5'; CharSetWidth: 1; CodePage: 
28595),
   (CharsetID: 36; CharSetName: 'ISO8859_6'; CharSetWidth: 1; CodePage: 
28596),
   (CharsetID: 37; CharSetName: 'ISO8859_7'; CharSetWidth: 1; CodePage: 
28597),
   (CharsetID: 38; CharSetName: 'ISO8859_8'; CharSetWidth: 1; CodePage: 
28598),
   (CharsetID: 39; CharSetName: 'ISO8859_9'; CharSetWidth: 1; CodePage: 
28599),
   (CharsetID: 40; CharSetName: 'ISO8859_13'; CharSetWidth: 1; CodePage: 
28603),
   (CharsetID: 41; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 42; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 43; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 44; CharSetName: 'KSC_5601'; CharSetWidth: 2; CodePage: 949),
   (CharsetID: 45; CharSetName: 'DOS852'; CharSetWidth: 1; CodePage: 852),
   (CharsetID: 46; CharSetName: 'DOS857'; CharSetWidth: 1; CodePage: 857),
   (CharsetID: 47; CharSetName: 'DOS861'; CharSetWidth: 1; CodePage: 861),
   (CharsetID: 48; CharSetName: 'DOS866'; CharSetWidth: 1; CodePage: 866),
   (CharsetID: 49; CharSetName: 'DOS869'; CharSetWidth: 1; CodePage: 869),
   (CharsetID: 50; CharSetName: 'CYRL'; CharSetWidth: 1; CodePage: 1251),
   (CharsetID: 51; CharSetName: 'WIN1250'; CharSetWidth: 1; CodePage: 1250),
   (CharsetID: 52; CharSetName: 'WIN1251'; CharSetWidth: 1; CodePage: 1251),
   (CharsetID: 53; CharSetName: 'WIN1252'; CharSetWidth: 1; CodePage: 1252),
   (CharsetID: 54; CharSetName: 'WIN1253'; CharSetWidth: 1; CodePage: 1253),
   (CharsetID: 55; CharSetName: 'WIN1254'; CharSetWidth: 1; CodePage: 1254),
   (CharsetID: 56; CharSetName: 'BIG_5'; CharSetWidth: 2; CodePage: 950),
   (CharsetID: 57; CharSetName: 'GB_2312'; CharSetWidth: 2; CodePage: 936),
   (CharsetID: 58; CharSetName: 'WIN1255'; CharSetWidth: 1; CodePage: 1255),
   (CharsetID: 59; CharSetName: 'WIN1256'; CharSetWidth: 1; CodePage: 1256),
   (CharsetID: 60; CharSetName: 'WIN1257'; CharSetWidth: 1; CodePage: 1257),
   (CharsetID: 61; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 62; CharSetName: 'Unknown'; CharSetWidth: 0; CodePage: 
CP_NONE),
   (CharsetID: 63; CharSetName: 'KOI8R'; CharSetWidth: 1; CodePage: 20866),
   (CharsetID: 64; CharSetName: 'KOI8U'; CharSetWidth: 1; CodePage: 21866),
   (CharsetID: 65; CharSetName: 'WIN1258'; CharSetWidth: 1; CodePage: 1258),
   (CharsetID: 66; CharSetName: 'TIS620'; CharSetWidth: 1; CodePage: 874),
   (CharsetID: 67; CharSetName: 'GBK'; CharSetWidth: 2; CodePage: 936),
   (CharsetID: 68; CharSetName: 'CP943C'; CharSetWidth: 2; CodePage: 943),
   (CharsetID: 69; CharSetName: 'GB18030'; CharSetWidth: 4; CodePage: 
54936)