dll中ado连接的实现

关键词:DLL ADO连接
//dll主程序
library erpsend;
uses
SysUtils,
Classes,
Forms,
msgdata in 'msgdata.pas' {data: TDataModule};
{$R *.res}
function msgsend(MsgNo:Integer;AccNo:String;sAccNo:String;sName:String;sDepNo:
String;sDepName:String;SysName:String;msg:string):Integer;stdcall;
begin
try
//根据参数更新SQL server
with data.Tmsg do
begin
append;
FieldByName('MsgNo').AsInteger:=MsgNo;
FieldByName('AccNo').AsString:=AccNo;
FieldByName('sAccNo').AsString:=sAccNo;
FieldByName('sName').AsString:=sName;
FieldByName('sDepNo').AsString:=sDepNo;
FieldByName('sDepName').AsString:=sDepName;
FieldByName('SysName').AsString:=SysName;
FieldByName('sMsgTxt').AsString:=msg;
FieldByName('sTime').AsString:=FormatDateTime('yyyy/mm/dd hh:mm',now);
post;
end;
msgsend:=1;//成功返回1
except
msgsend:=0;//失败返回0
end;
end;
exports
msgsend INDEX 1;
begin
Application.CreateForm(TData, Data);//dll调用时自动初始化数据ado连接
end.
//数据模块DataModule单元
unit msgdata;
interface
uses
SysUtils, Classes, DB, ADODB,Dialogs;
type
Tdata = class(TDataModule)
ADOCon: TADOConnection;
Tmsg: TADOTable;
procedure DataModuleCreate(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
data: Tdata;
implementation
{$R *.dfm}
procedure
Tdata.DataModuleCreate(Sender: TObject);
begin
try
with ADOCon do //动态建立与sql server 连接
begin
ConnectionString:='Provider=SQLOLEDB.1;Persist Security Info=True;Initial Catalog=erpmsg;Data Source=bill';
{其中:erpmsg为数据库名,bill为服务器名}
Open('erpuser','erp');
{其中:erpuser为用户名,erp这密码}
end;
tmsg.TableName:='msgtxt';
tmsg.active:=true;
{若此处读取外部配置文件,如ini文件,可实现SQL主机、用户、密码等信息的灵活修改 }
except
SHOWMESSAGE('连接数据服务器失败！');
end;
end;
end.
这样就可以在一些对ado支持不好的语言如vfp等中实际ado数据连接与更新,避免了客户端odbc设置,不过在用户计算机上要设一下sql客户端,最简单的办法是写入如下注册表信息:
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer\Client]
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer\Client\ConnectTo]
"BILL"="DBMSSOCN,BILL,1433"
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer\Client\DB-Lib]
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer\Client\TDS]
"BILL"="7.0"
(以上为Win2000注册表格式,Win98类似)