Liren Large Software Subsidy 5

home *** CD-ROM | disk | FTP | other *** search

/ Liren Large Software Subsidy 5 / 05.iso / a / a082 / 1.img / README.TXT < prev

Wrap

Text File | 1994-01-14 | 21.7 KB | 572 lines

README.TXT ********************************************************** Release Notes for Microsoft(R) FoxPro(R) for MS-DOS (R) Version 2.5b (C)1993 Microsoft Corporation. All Rights Reserved. Information in the FoxPro online Help is more current than information in the printed documentation. This README provides information not contained in the FoxPro online help or documentation, and provides corrections to both. ********************************************************** ======== CONTENTS ======== Part Description ---- ----------- 1 Installation 2 WAIT...WINDOW Enhancements 3 New Commands and Functions 4 New Transporter and Screen Directives 5 International and Cross-Platform Recommendations ---------------------------------------------------------- ==================== Part 1: Installation ==================== There are three types of installation for FoxPro for MS-DOS: Normal Installation, Administrative Installation and Workstation Installation. Instructions for Normal Installation are in the FoxPro Installation and Configuration manual. For information about Administrative and Workstation Installation, see INSTALL.TXT on FoxPro for MS-DOS Disk 1. ---------------------------------------------------------- ================================ Part 2: WAIT WINDOW Enhancements ================================ WAIT WINDOW now supports multiple line messages. Use a carriage return (CHR(13)) to move portions of your message to additional lines. The message window is automatically expanded to accommodate additional lines. For example, this command creates a message window that contains two lines: WAIT WINDOW "This is the 1st line" + CHR(13) + ; "This is the 2nd line" The width of the message window is adjusted to fit the longest line in the message. All lines in the message are left justified in the message window. Line feeds (CHR(10)) following CHR(13) are ignored. ---------------------------------------------------------- ================================== Part 3: New Commands and Functions ================================== Several new commands and functions are added to FoxPro 2.5b. For additional information about these commands and functions, see the "International and Cross Platform Recommendations" section below and the corresponding topics in Help. New Commands ------------ SET NOCPTRANS SET COLLATE New Functions ------------- CPCURRENT( ) CPDBF( ) CPCONVERT( ) IDXCOLLATE( ) ---------------------------------------------------------- ============================================= Part 4: New Transporter and Screen Directives ============================================= Several new Transporter and screen directives have been added. The #DOSOBJ, #MACOBJ, #UNIXOBJ and #WINOBJ Transporter directives allow you to transport objects created in the Screen Builder and Report Writer to specific FoxPro platforms. For additional information about these Transporter directives, see the Transporting Files topic in Help. #TRAN SNIPPET ONLY, a new screen directive, is available in FoxPro 2.5b. This screen directive affects how screen objects are transported, and is not discussed in Help. #TRAN SNIPPET ONLY is designed to limit the Transporter's changes to just screen snippets, and is placed in a screen's Setup snippet. When screen objects are transported to a different FoxPro platform, only the screen snippets for updated screen objects are transported if #TRAN SNIPPET ONLY is included. All other screen object attributes are not transported to the different platform. Note that #TRAN SNIPPET ONLY only affects updated screen objects; it does not affect new or unchanged screen objects or screen objects being transported for the first time. ---------------------------------------------------------- ========================================================= Part 5: International and Cross Platform Recommendations ========================================================= *** IMPORTANT *** ******************************************************* * Be sure to read this section completely before you * * change code pages or collation sequences! * ******************************************************* Overview of topics 1 FoxPro Collation Sequences 2 Case-Insensitive Collation Sequences 3 Case-Sensitive Collation Sequences 4 How do the SEEK and SKIP commands work? 5 Alternatives to SEEK and SKIP 6 Additional Recommendations 7 New Code Pages 8 CPZERO Program 9 Corrections to the Help File FoxPro 2.5b gives international developers and users powerful new features for handling accented characters across different FoxPro platforms, and provides accurate sorting in many languages. For international FoxPro users, this section describes how code pages and collation sequences affect sorting, seeking and comparisons using the SORT and SEEK commands, and also provides recommendations for taking advantage of these features. U.S. FoxPro users whose applications don't contain accented characters may not need any of the new international 2.5b features. In this case, you can disregard this section of the README and the International/X-Platform topic in Help. FoxPro 2.5b is 100% percent compatible with FoxPro 2.5. 1 FoxPro Collation Sequences ---------------------------- With a MACHINE collation sequence, which earlier FoxPro versions use (and to which FoxPro 2.5b still defaults), each character in the code page, whether it's a Roman character, an accented character, or a line-drawing character, has a unique "sort weight" determined by its position in the code page. In a majority of code pages, all accented characters appear after the unaccented characters. In this situation an ä sorts after z, which isn't correct in most languages (although it is true in Swedish, for instance). Furthermore, in most languages accented characters sort after their unaccented counterparts, but only if the unaccented versions of all characters being compared are the same. For example, in German, ä sorts after the unaccented a, but the string äa sorts before the string ab because the second character a is less than the second character b. In this way, characters are interleaved in many cultures. FoxPro 2.5b supports a number of new collation sequences to correctly sort in many languages. These sequences take into account all the complex rules of the language (including two-to-one, three-to-one and one-to-two mappings). The following collation sequences were available when this README was created. The code pages for which these collation sequences are defined are also included. Collation Sequence Friendly Name Code Pages ------------------ ------------- ---------- CZECH Czech 852, 895, 1250 DUTCH Dutch 437, 850, 1252 GREEK Greek 737, 1253 GENERAL General 437, 620, 850, 852, 861, 865, 895, 1250, 1252, 10000 HUNGARY Hungarian 852, 1250 ICELAND Icelandic 437, 850, 861, 1252 MACHINE Machine All NORDAN Norwegian/Danish 437, 850, 865, 1252 POLISH Polish 620, 852, 1250 RUSSIAN Russian 866, 1251 SLOVAK Slovak 852, 895, 1250 SPANISH Spanish 437, 850, 1252 SWEFIN Swedish/Finnish 437, 850, 1252 UNIQWT Unique Weight 437, 850, 1252, 10000 If you specify a collation sequence in the SET COLLATE command as a string literal, enclose the collation sequence in quotation marks. Don't enclose the collation sequence in quotation marks if you specify a collation sequence in your FoxPro configuration file (CONFIG.FP or CONFIG.FPW). If you use the SET COLLATE command to specify a collation sequence that isn't supported by the current code page, FoxPro generates an error. If you specify a collation sequence in your FoxPro configuration file that isn't supported by the current code page, the collation sequence defaults to MACHINE. If you specify a collation sequence in the International panel in the View window, the collation sequence names appear in longer forms. For example, the NORDAN option appears as Norwegian & Danish, and the SWEFIN option appears as Swedish & Finnish. For additional information about collation sequences, see SET COLLATE in Help. 3 Case-Sensitive Collation Sequences ------------------------------------ Two case-sensitive collation sequences are available in FoxPro: the familiar MACHINE sequence, the default sequence in earlier FoxPro versions, and the sequence named UNIQWT. UNIQWT is a "unique weight" sort in which each accented character sorts strictly after its unaccented counterpart (unlike the interleaving of accented characters described earlier). While the collation sequence with UNIQWT isn't strictly culturally correct as with GENERAL, it may aid developers in migrating their applications from earlier FoxPro versions. One reason is that upper- and lower-case letter are treated distinctly as they were in earlier FoxPro versions. Another reason is described in the section titled "How do the SEEK and SKIP commands work?" 4 How do the SEEK and SKIP commands work? ----------------------------------------- The SEEK command accepts an expression. FoxPro transforms that expression into a sort key which it compares to keys in the master index or tag. SEEK then positions the record pointer at the first index entry that's greater than or equal to ( >= ) the supplied key. With a machine sort, SEEK finds a match if there is one. The UNIQWT sort has the same property. But when FoxPro uses the new language-specific collation sequences to create indexes, only the alphabetic part of the key is considered and any diacritical marks are ignored. In other words, even if you SEEK "äbc" you may find "abc". Note that partial searches (where you search for part of the field) using SEEK may not return the results you expect when the current collation sequence is not MACHINE or UNIQWT. FoxPro behaves this way for the following three reasons: 1) Performance. 2) Consistency with the SKIP command. 3) Consistency with the SET NEAR command. To have SEEK and SKIP find only those records that exactly match accented characters, you must either SET EXACT ON or use an index tag created with the MACHINE or UNIQWT collation sequences. Note that SEEK and SKIP use the collation sequence of the master index or tag, and ignore the current collation sequence. SEEK can't be used unless there is an index is active. 5 Alternatives to SEEK and SKIP ------------------------------- If you use accented characters, use one of the following methods to search a table: 1) Construct a loop with SCAN FOR ... ENDSCAN. 2) Use LOCATE FOR ... CONTINUE. LOCATE and SCAN use an index if one is active, and they have two very significant advantages over SEEK when data contains accented characters. First, both LOCATE and SCAN remember the condition with which they were invoked, so they can be used for looping on a condition. SEEK, on the other hand, simply positions you somewhere in the index, and SKIP continues down the index from that point. With international data, this may not give you the results you want. Second, LOCATE and SCAN are diacritically-sensitive, whereas SEEK isn't. In addition, both LOCATE and SCAN can be fully optimized by Rushmore if the current collation sequence is MACHINE or UNIQWT; otherwise partial optimization will occur. The ORDER BY clause of the SQL SELECT command uses the current collating sequence, which is returned by SET("COLLATE")). 6 Additional Recommendations ---------------------------- 1) If you aren't concerned with indexing accented characters in a language-specific way, feel free to continue to use machine indexes. For many U.S. users, this is appropriate. 2) For the best performance when using a collation sequence other than MACHINE or UNIQWT, be sure that the current collation sequence is the same as the collation sequence of any indexes you are using. 3) Most international users will want accented characters in all fields to be translated automatically by FoxPro when running cross-platform applications. However, if you have a table with a character field that's actually storing binary information (data), the SET NOCPTRANS command allows you to inform FoxPro that characters in such a field should not be translated. Binary data might otherwise be changed, because of FoxPro's "nearest" character mapping. For characters such as the MS-DOS line-drawing characters, FoxPro maps to the "nearest" character in the destination code page. If you choose to use SET NOCPTRANS, you must do so immediately after issuing the USE command. From that point on, FoxPro's automatic character translation is not in effect for any fields you designate. In particular, you must issue the SET NOCPTRANS command before issuing a SQL SELECT command -- you cannot let SQL SELECT open tables for you if the tables contain fields which should not be translated. Note that SET NOCPTRANS only operates on fields for the table open in the currently selected work area. If you close a table and then open the table again, you must reissue SET NOCPTRANS and designate the fields which should not be translated. 4) If you create cross platform applications, you should avoid using FoxFont. FoxFont is an OEM MS-DOS font that you may find useful in some situations. But if you use FoxFont in an application you create in FoxPro for Windows, some of the characters in the application may not transport correctly to other FoxPro platforms. Furthermore, FoxFont won't correctly display characters typed on international Windows keyboards. If you have automatic code page translation enabled, FoxPro will display accented characters correctly. FoxFont is the installed default font for the FoxPro desktop. FoxFont is the default font for user-defined windows created with DEFINE WINDOW when the FONT clause is omitted. Be sure to include the FONT clause when creating user-defined windows in FoxPro for Windows. FixedSys is the default font for the Command, Trace and Debug windows if you're using Windows 3.1. Text editor windows default to the current Command window font. 5) FoxPro 2.5b can automatically translate accented characters in most files types such as .DBF, .SCX, and .FXP files. However, program (.PRG) and text (.TXT) files don't have a header and can't be marked with a code page. Therefore, FoxPro must assume that a program or text file was designed for use on the platform on which it is opened. It's important that you compile each program on the platform on which it was written. Since compiled programs (.FXP files) have a header, once you compile a program, it can be run on any FoxPro platform and accented characters in the original source program are automatically translated when automatic code page translation is in effect. 6) Do not mix programs created on different FoxPro platforms in a project. The Project Manager assumes that all programs in a project are native to the current FoxPro platform. If you create an application or an executable from a project that contains programs created on different FoxPro platforms, translation of accented characters in the programs might not be translated properly. Also, within the Project Manager you can't specify the platform on which a program or text file was created. Therefore, in the Project Manager don't edit programs or tables created on a FoxPro platform other than the current platform. This means that you shouldn't double-click on a file to open it in the Project Manager if you've enabled automatic translation by including CODEPAGE = AUTO in your FoxPro configuration file. If you create an application that contains files created on different FoxPro platforms, do not open the files for editing from within the Project Manager. However, once you build an application (.APP file), it will run on any FoxPro platform and FoxPro can automatically translate accented characters. 7) If you have a project created in FoxPro for MS-DOS version 2.0 and the files within the project contain accented characters, you can share the project and its files across different FoxPro platforms by performing the following steps to convert the project and its files. This conversion is required just once, and enables cross platform sharing of all the elements of the project. a) Open the project in FoxPro for MS-DOS 2.5b or FoxPro for Windows 2.5b. A dialog appears, asking if you would like to convert the project to a 2.5 format. Choose Yes, then close the project. b) Open every screen, report, label, menu and table contained in the project with the USE command. You are prompted for the code page (437, 850 and so on) on which each was created. Specify the MS-DOS code page on which each was built and then choose Yes. c) Use MODIFY COMMAND or MODIFY FILE and include the AS clause to open EVERY program, query, format file or text file contained in the project. In the AS clause, specify the code page (437, 850 and so on) of the FoxPro platform on which each was created. Choose the Save As option from the File menu and choose the Change Code Page check box. In the dialog that appears after you choose Save, specify the code page for the FoxPro platform on which the file will be used. 8) If you're developing a cross-platform application, avoid using characters that appear in one code page and not another. For example, the MS-DOS line drawing characters aren't supported under Windows, so avoid using them in screens you plan to transport between FoxPro for MS-DOS and FoxPro for Windows. You can use CHR() if your application absolutely requires line drawing and accented characters. Output from CHR() isn't translated when the function is executed, allowing you to output any character. 9) The MS-DOS file system is case-insensitive and requires uppercase file names. If your applications run on FoxPro for MS-DOS, be sure to restrict file names to those characters that have uppercase equivalents in your MS-DOS code page. For example, code page 437 doesn't contain uppercase versions of several accented vowels. These characters can't be safely used in a FoxPro file name. It's best to avoid accented characters in file names. 7 New Code Pages ---------------- The following code pages are now supported: Code Page Platform --------- -------- 437 U.S. MS-DOS 737 Greek MS-DOS (437G) 620 Mazovia (Polish) MS-DOS 850 International MS-DOS 852 EE MS-DOS (Latin II) 861 Icelandic MS-DOS 865 Nordic MS-DOS 866 Russian MS-DOS 895 Kamenicky (Czech) MS-DOS 1250 Windows EE 1251 Russian Windows 1252 Windows ANSI 1253 Greek Windows 10000 Standard Macintosh Byte 29 in table headers contains the code page identifier. The following table lists the code page and the corresponding code page identifier in hex. Code Page Code Page Identifier --------- -------------------- 437 x01 737 x6A 620 x69 850 x02 852 x64 861 x67 865 x66 866 x65 895 x68 1250 xC8 1251 xC9 1252 x03 1253 xCA 10000 x04 8 CPZERO Program ---------------- If you accidentally specify the wrong code page when you open a table that isn't marked with a code page, run CPZERO.PRG to reset the table's code page to zero. CPZERO is a FoxPro program that is automatically installed in your FoxPro directory. Before you run CPZERO, make sure that the table whose code page you'll reset isn't open. When you run CPZERO, you are prompted for the name of the table to modify. 9 Corrections to the Help File ------------------------------ Configuring FoxPro and International/X-Platform Topics ------------------------------------------------------ These FoxPro 2.5b help file topics contain the following line: "Note that MODIFY STRUCTURE also marks a table with the current code page." This line is incorrect and should read: "Note that MODIFY STRUCTURE doesn't mark a table with the current code page. Rather, it preserves the table's existing code page mark." International/X-Platform Topic ------------------------------ This help file topic contains the following line: For example, if the current collation sequence is GENERAL, both of these return true (.T.): "Straße" = "Strasse" and "Straße" == "Strasse" "Straße" == "Strasse" will always return .F., not .T. as it states in this topic. A strict machine comparison is performed by ==. All characters in each string are compared, including trailing blanks. For more information about comparisons using = and ==, see SET EXACT in the Language Reference or the FoxPro help facility. ---------------------------------------------------------- ================= End of README.TXT =================