.NET的數(shù)據(jù)庫天然支持MSSQLServer,但是并非其他數(shù)據(jù)庫不支持,而是微軟基于自身利益需要,在支持、營銷上推自己的數(shù)據(jù)庫產(chǎn)品;但是作為平臺戰(zhàn)略,他并非排斥其他數(shù)據(jù)庫,而是參考java體系提出了一套數(shù)據(jù)庫訪問規(guī)范,讓各個第三方進行開發(fā),提供特定的驅(qū)動。新疆軟件開發(fā)網(wǎng)搜集整理 Cq3pXq{G CkS8rX' MySQL是免費的數(shù)據(jù)庫,在成本上具有無可替代的優(yōu)勢,但是目前來講,并沒有提供。微軟把MySQL當作ODBC數(shù)據(jù)庫,可以按照ODBC.Net規(guī)范進行訪問,具體參考 Y.gASJL/` u q_&*$ http://www.microsoft.com/china/community/Columns/Luyan/6.mspx 7s'uHx m.6D^J! 而實際上,針對ODBC。Net的需要配置DSN的麻煩,而是出現(xiàn)了一個開源的系統(tǒng)MySQLDriverCS,對MySQL的開發(fā)進行了封裝,實現(xiàn)了.net環(huán)境下對于MySQL數(shù)據(jù)庫系統(tǒng)的訪問。 z}@&%"' 9Ljkl=Ppc http://sourceforge.net/projects/mysqldrivercs/ "Lu,8Eq d mWqvP/D 通過閱讀源代碼,我們看到MySQLDriverCS的思路是利用C函數(shù)的底層庫來操縱數(shù)據(jù)庫的,通常提供對MySQL數(shù)據(jù)庫的訪問的數(shù)據(jù)庫的C DLL是名為libmySQL.dll的驅(qū)動文件,MySQLDriverCS作為一個.net庫進行封裝C風(fēng)格的驅(qū)動。 hg1; I( MeVKx5 y 具體如何進行呢? vR K:: 1l]kskJ>D 打開工程后,我們看到其中有一個比較特殊的.cs文件CPrototypes.cs: W}^NH/7E ^l.{S%|4 以下是引用片段: 8o20:OA,X Xar*yE;e #region LICENSE c!9zei /* Tc%a6F:Ke MySQLDriverCS: An C# driver for MySQL. ?2kVCs&>5 Copyright (c) 2002 Manuel Lucas Vi馻s Livschitz. a0&-H{=/z 3^xuVUDX This file is part of MySQLDriverCS. Y4a4/XEa 5Kd1IP MySQLDriverCS is free software; you can redistribute it and/or modify 4C`n2{i it under the terms of the GNU General Public License as published by d.yK?Fj the Free Software Foundation; either version 2 of the License, or :TNdqHcv (at your option) any later version. |VR;,aE%\ abQ{Qw& MySQLDriverCS is distributed in the hope that it will be useful, vg5T{~XN but WITHOUT ANY WARRANTY; without even the implied warranty of )I{<E m3 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the {z>H&,`n GNU General Public License for more details. A.|o {> |K{5W(t. You should have received a copy of the GNU General Public License I[ELwFt {W along with MySQLDriverCS; if not, write to the Free Software p17YBfC Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA }CVb'2 $1 */ 0<ZV),<c #endregion Xh ><glF using System; vN2n\M^J^ using System.Data; A~wZ2I@^ using System.Runtime.InteropServices; Bz.Pc); namespace MySQLDriverCS P7'ztDm" { zr/#73q&L Z' iD_mtZ //[StructLayout(LayoutKind.Sequential)] sS>v%`_ public class MYSQL_FIELD_FACTORY 9y7:F (1 { ~wNU=*,O static string version; x}o{' public static IMYSQL_FIELD GetInstance() {z-8\LH s { =3R l\ E"t\! eSW if (version==null) u,E*WcM/ { Hl& Fh0k version = CPrototypes.GetClientInfo(); `TG[y 0m } * ^'E if (version.CompareTo("4.1.2-alpha")>=0) x_}JRcny^ { {TU;3DR return new MYSQL_FIELD_VERSION_5(); \|&;b<S! } Gg?rNB < else SxY-C{gR return new MYSQL_FIELD_VERSION_3(); D8Gp1H } m o|O`UG\ } N#UAoGIt; public interface IMYSQL_FIELD !Lo?oG+ { pPk 9le string Name{get;} @ 0u9` uint Type{get;} 6eF~u.i long Max_Length {get;} g~NzFv=:G } J 7\lW U ///<summary> gFI/X!k% /// Field descriptor ={k|[:S ///</summary> Ks*xm1l3 [StructLayout(LayoutKind.Sequential)]//"3.23.32", 4.0.1-alpha x24L"hJCK internal class MYSQL_FIELD_VERSION_3: IMYSQL_FIELD Bs338 s{} { lD~XV:+ ///<summary> jU3x@?JH /// Name of column |D 7PRio ///</summary> li:UK][l@ public string name; *\vn1`% ///<summary> d@wVr A! /// Table of column if column was a field 9Y<Z}E$g9 ///</summary> c|7@^h` public string table; KJOh/.mM //public string org_table; /* Org table name if table was an alias */ E ^eS //public string db; /* Database for table */ \uNZ&qy( ///<summary> ~k!qd9YN3 /// def "%qp?R-zy ///</summary> x|* y;dB public string def; Y'% s'k ///<summary> ^xv<MQ^N /// length hAL Ul/_ ///</summary> eUl0Q public long length; _]=K&~@/s ///<summary> !@"i+8]6V /// max_length BkaMb,~ ///</summary> ,CpX fEm public long max_length; =$IYhuS~ ///<summary> O4pj~uQ7 /// Div flags L+]=g(@E ///</summary> \,| 3p public uint flags; %ty'Z&&k ///<summary> MXF>HW /// Number of decimals in field MyeO+IF2 ///</summary> $;bff"bO public uint decimals; $4ht`R ///<summary> =0) C3:q /// Type of field. Se mysql_com.h for types ka-n[Hz ///</summary> W]]-NWk public uint type; t.!9<p => |3e' 5jf$ ///<summary> %q!1M-8 /// Name V/ hP ///</summary> <L{Vx+0I public string Name !%L~p]|w { 1oe C&se get{return name;} ^h5qUrulL } EmT{#o9 ///<summary> a cU#;]"s /// Type # !!MQTk ///</summary> P`a-C3FF public uint Type K4u$4)as { P LHr) get{return type;} @uync8?% } cp)NZWz ///<summary> g=?e3 . /// Max_Length V#@ VsgKK ///</summary> # L h~CpnS public long Max_Length CJ"Be'u Xy { 2H*2N= get {return max_length;} \gTV[OB } ~$?~NiZ,) } +`xIuic -fu}K W ///<summary> ~`fOP Q /// Field descriptor HR~+yFp8 ///</summary> _;{_m{u [StructLayout(LayoutKind.Sequential)] u>^|OcW internal class MYSQL_FIELD_VERSION_5: IMYSQL_FIELD cJ|h=mv { T&"ao4Io} ///<summary> /T\|=Q /// Name of column z QP*t~ ///</summary> OC;|% s#m public string name; pM`#7lE ///<summary> 4^Kk?ib}L /// Original column name, if an alias ,AhB !( ///</summary> @SKjhi public string org_name; tn6$Px ///<summary> : +S>8 /// Table of column if column was a field j vA%b ///</summary> %LO&\{,1U public string table; `#'kUYQ[] ///<summary> }ifhThTa /// Org table name if table was an alias 'shu2( ///</summary> e9n3sv/ public string org_table; oL /UPl`7s ///<summary> gRUxL /// Database for table %q0D+[ TV ///</summary> wh c fX public string db; Ga+v@,J1 ///<summary> c~ zR(BO /// Catalog for table 7yOn''N ///</summary> s]o o~DX //public string catalog; '.3l 8! ///<summary> 9 *iRa %:^ /// def 4e6Pm : ///</summary> c_OFJ3n!n public string def; i'{<D7( ///<summary> &6&PjZfIL /// length YUubM"7 ///</summary> a$"z$<Y. public long length; 1s n7xaj ///<summary> y$?8_L /// max_length 9bf0+h)9 ///</summary> i4rkoekJ public long max_length; AW9j3UE ///<summary> 5+~' R{~~ /// name_length Ic3BE2r ///</summary> }^-uv;d\ //public uint name_length; ]x~OXF'I~ ///<summary> !G5)q> { /// org_name_length *AYo\u ///</summary> ^. _|FT public uint org_name_length; |u]S)TcVju ///<summary> lF_DBPFko /// table_length d_})1S~SB ///</summary> t & v public uint table_length; PB.LF ///<summary> A@M &ah : /// org_table_length Ws[LxBkE ///</summary> R#NamBWl public uint org_table_length; Fo` lo.)*] ///<summary> IY:EX#) /// db_length p $zIXQ( g ///</summary> q`YSi public uint db_length; 38<39Lz ///<summary> rK2HZ 5 /// catalog_length 'xTgSf. ///</summary> 5Do& #G9 public uint catalog_length; -@K*sQ ///<summary> ;2dxdUUQj /// def_length -SmSW / ///</summary> @.c(LzxKc public uint def_length; 4=M-fv%# ///<summary> NM ?F7b]? /// Div flags jq26D$>K ///</summary> {.,'>hw>U public uint flags; ,Tl:9y?2 ///<summary> /%8jto( /// Number of decimals in field XoPL-GBa ///</summary> 5 /[s^/eE public uint decimals; ;WR%0fp' ///<summary> NYA^xh /// Character set G}Vh;%T# ///</summary> -=]HbX@i public uint charsetnr; ?Rvu` ///<summary> U!w11P /// Type of field. Se mysql_com.h for types hFch#a-; ///</summary> ua#[^I+& public uint type; g{\.V( _VXg0 ///<summary> #[}2KA QLx /// Name ML[?hj ///</summary> (njL[#u2 public string Name J0 {iXI { p*%pk= get {return name;} E'Sy d\ } +n%73= ///<summary> 8:o" /// Type odNkG:R. ///</summary> "?{2) +G public uint Type Oi) 5r}f { Y3:5YSTk get {return type;} >y"tuh5:H } %^W.i"H0f ///<summary> *b,:5lKXK /// Max_Length D,R{vjP- ///</summary> bZ>6V0{= public long Max_Length w,lz]Y, { Fcbf"T2J get {return max_length;} 4>8#Q0 } qaLYL`ak } !]EC`]zYj //[StructLayout(LayoutKind.Explicit)] c|*`s.gh public enum enum_field_types +vN".EU { $hsOZdR FIELD_TYPE_DECIMAL, FIELD_TYPE_TINY, oCCa FIELD_TYPE_SHORT, FIELD_TYPE_LONG, "b.gK6 FIELD_TYPE_FLOAT, FIELD_TYPE_DOUBLE, >*l2R6qzn FIELD_TYPE_NULL, FIELD_TYPE_TIMESTAMP, ,2y8( FIELD_TYPE_LONGLONG,FIELD_TYPE_INT24, +;G^bx_ #| FIELD_TYPE_DATE, FIELD_TYPE_TIME, @?@J; FIELD_TYPE_DATETIME, FIELD_TYPE_YEAR, RDFx i=&a FIELD_TYPE_NEWDATE, b?eIjkn FIELD_TYPE_ENUM=247, e!J|c^c5' FIELD_TYPE_SET=248, x [c2/a_X FIELD_TYPE_TINY_BLOB=249, $f0c'%UW FIELD_TYPE_MEDIUM_BLOB=250, 5Qd_2e` FIELD_TYPE_LONG_BLOB=251, \kvZ/>G3xZ FIELD_TYPE_BLOB=252, 6p\=sL FIELD_TYPE_VAR_STRING=253, 6tN!'l+P FIELD_TYPE_STRING=254, 2wh/# FIELD_TYPE_GEOMETRY=255 m mZ. V3}PXO=C }; *7FLogi Vs?"@'g& ///<summary> r?-2sCQF /// C prototypes warpper for mysqllib. ]3|LTB=wO ///</summary> `I/ub internal class CPrototypes \!f YFt { %eW`W/i] [ DllImport( "libmySQL.dll", EntryPoint="mysql_init" )] jZ-PZMhFl unsafe public static extern void* mysql_init(void* must_be_null); r1]5!0EvNB [ DllImport( "libmySQL.dll", EntryPoint="mysql_close" )] Su$Pi unsafe public static extern void mysql_close(void* handle); @vS xG$Tz "9i5TpH1 // BEGIN ADDITION 2004-07-01 BY Alex Seewald YQC8O Q // Enables us to call mysql_option to activate compression and timeout Uamz\o [ DllImport( "libmySQL.dll", EntryPoint="mysql_options" )] 5 k.D8%M unsafe public static extern void mysql_options(void* mysql, uint option, uint *value); fMFUyx!L // END ADDITION 2004-07-01 By Alex Seewald V4:Qd~+} [ DllImport( "libmySQL.dll", EntryPoint="mysql_real_connect" )] ]t}}T ' unsafe public static extern void* mysql_real_connect(void* mysql, string host, string user, string passwd, string db, uint port, string unix_socket, int client_flag); ";b`Dt-9k [ DllImport( "libmySQL.dll", EntryPoint="mysql_query" )] 17Yzeyo unsafe public static extern int mysql_query(void*mysql, string query); ErSB8FL] [ DllImport( "libmySQL.dll", EntryPoint="mysql_store_result" )] 4:l5+$ unsafe public static extern void *mysql_store_result(void *mysql); ct$7{ 9 [ DllImport( "libmySQL.dll", EntryPoint="mysql_free_result" )] 6pkNC\a unsafe public static extern void mysql_free_result(void*result); ;(n0) [ DllImport( "libmySQL.dll", EntryPoint="mysql_errno" )] yM6{+<} unsafe public static extern uint mysql_errno(void*mysql); _+BIqsZ[8q [ DllImport( "libmySQL.dll", EntryPoint="mysql_error" )] Mr)GhH.\ unsafe public static extern string mysql_error(void*mysql); ?rIqSfE_ [ DllImport( "libmySQL.dll", EntryPoint="mysql_field_count" )] }yq unsafe public static extern uint mysql_field_count(void*mysql); bn3&D^"! [ DllImport( "libmySQL.dll", EntryPoint="mysql_affected_rows" )] Xd?.}9| unsafe public static extern ulong mysql_affected_rows(void*mysql); S*~ >6>2P [ DllImport( "libmySQL.dll", EntryPoint="mysql_num_fields" )] Zl6Kr8T5 unsafe public static extern uint mysql_num_fields(void*result); !cI{j(_ [ DllImport( "libmySQL.dll", EntryPoint="mysql_num_rows" )] ;]S{Rw3K[ unsafe public static extern ulong mysql_num_rows(void *result); $rNRB: [ DllImport( "libmySQL.dll", EntryPoint="mysql_fetch_field_direct" )] S}Wmnx % unsafe public static extern IntPtr mysql_fetch_field_direct(void*result, uint fieldnr); x`((=! Ve`;7uY{s ///<returns>Returns a string that represents the client library version</returns> (ghqCOT Xl [DllImport("libmySQL.dll",CharSet=System.Runtime.InteropServices.CharSet.Ansi, c12`"Ng EntryPoint="mysql_get_client_info", ExactSpelling=true)] W!grr}4OU9 public static extern string GetClientInfo(); =q>F* !(N G8_AS| [ DllImport( "libmySQL.dll", EntryPoint="mysql_fetch_row" )] w$@:Ss[d unsafe public static extern IntPtr mysql_fetch_row(void*result); cRhkNI$ [ DllImport( "libmySQL.dll", EntryPoint="mysql_select_db" )] 0n O38 unsafe public static extern int mysql_select_db(void*mysql,string dbname); W[VeoO [ DllImport( "libmySQL.dll", EntryPoint="mysql_fetch_lengths" )] }tI` n Hc unsafe public static extern UInt32 *mysql_fetch_lengths(void*result); knVy6H jTE:i:aZN } a]pC6(g } m.r5 4(t =m"KiJ46 q0tu$ j 基本上是將C風(fēng)格的基礎(chǔ)數(shù)據(jù)結(jié)構(gòu)進行.net的重新定義,然后通過InteropServices進行訪問。 n KcJ#y9 lb{XRgdXDL 具體如何利用這個庫進行操作,可以參考其中的例子。
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