delphi+access项目开发笔记

一、Delphi连接ACCESS的方法在窗体中加ADOQuery1，ADOConnection1。（ADO标签内）ADOConnection1中属性ConnectionString连接到你的数据库（选择连接到你的数据库路径）；ADOQuery1控件中属性Connection为ADOConnection1。在窗体创建的时候设置数据库连接字符串（access带密码）：procedureTForm3.FormCreate(Sender:TObject);beginADOConnection1.ConnectionString:='Provider=Microsoft.Jet.OLEDB.4.0;DataSource='+ExtractFilePath(Application.EXEName)+'database/test.mdb;PersistSecurityInfo=False;'+'JetOLEDB:DatabasePassword=159753';end;二、Delphi数据库集合循环操作(字符串截取、变量类型转换)ADOQuery2.SQL.Add('select*fromtable');ADOQuery2.Prepared;ADOQuery2.Open;ADOQuery2.first;whilenotADOQuery2.eofdobegin//开始循环t1:=copy(ADOQuery2.FieldByName('DZSJ').asstring,1,2);t2:=strtoint(t1);end;三、Delphi数据库查询、获得某字段的值ADOQuery4.Close;ADOQuery4.SQL.Clear;ADOQuery4.SQL.Add('select*fromtable);ADOQuery4.SQL.Add('whereYCH=:YCH1');ADOQuery4.Parameters.ParamByName('YCH1').Value:=Edit1.text;ADOQuery4.Prepared;ADOQuery4.Open;Edit2.text:=ADOQuery4.FieldByName('JS').asstring;ADOQuery4.Close;四、Delphi数据库写入值ADOQuery1.Close;ADOQuery1.SQL.Clear;ADOQuery1.SQL.Add('select*fromtable1');ADOQuery1.Prepared;ADOQuery1.Open;ADOQuery1.Append;ADOQuery1.FieldByName('name').asstring:=Edit1.Text;ADOQuery1.FieldByName('age').asstring:=Edit3.Text;tryADOQuery1.post;ADOQuery1.Close;Application.MessageBox('信息添加成功！','信息提示',64);exceptADOQuery1.Cancel;Application.MessageBox('信息添加失败！','错误',64);exit;end;五、Delphi文件复制（获取执行文件所在的目录[useStdCtrls,ExtCtrls,FileCtrl;]）ifFileExists(ExtractFilePath(Application.EXEName)+'image/'+filename)thenbeginApplication.MessageBox('文件已经存在！','错误提示',64);Exit;endelsebeginifCopyFile(pChar(picurl),pChar(ExtractFilePath(Application.EXEName)+'image/'+filename),false)thenbeginApplication.MessageBox('复制成功！','错误提示',64);endelsebeginApplication.MessageBox('复制失败！','错误提示',64);endend六、Delphi目录浏览（获取文件的文件名和目录[useStdCtrls,ExtCtrls,FileCtrl;]）varOpenDialog:TOpenDialog;beginOpenDialog:=TOpenDialog.Create(nil);OpenDialog.InitialDir:=ExtractFilePath(Application.EXEName);OpenDialog.Filter:='图片文件(*.jpg)|*.jpg';ifOpenDialog.Executethenbeginpicurl:=OpenDialog.FileName;filename:=ExtractFileName(picurl);filepath:=ExtractFileDir(picurl);end;end;七、Delphi目录浏览（获取目录[useStdCtrls,ExtCtrls,FileCtrl;]）varsDir:string;beginifSelectDirectory('',ExtractFilePath(Application.EXEName),sDir)then//已返回所选文件夹路径给sDir,自行处理Edit2.Text:=sDir;end;八、Delphi图片动态导入（[usesjpeg,ExtCtrls;]）Image1.Picture.LoadFromFile(ExtractFilePath(Application.EXEName)+'image/default.jpg');在实际项目中将文件名存储在一个字段中，需要使用时直接调用图片名。