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Delphi FireDAC 下的 Sqlite（九） 关于排序2015-02-13SQLite 内部是按二进制排序, 可以支持 ANSI; FrieDAC 通过 TFDSQLiteCollation 支持了 Unicode 排序, 并可通过其 OnCompare 事件自定义排序.下面的例子, 测试了这两种排序的不同.

可把下面代码直接贴在空白窗体上, 以快速完成窗体设计: object DBGrid1: TDBGrid Left = 0 Top = 0 Width = 297 Height = 199 Align = alLeft DataSource = DataSource1 TabOrder = 0 TitleFont.Charset = DEFAULT_CHARSET TitleFont.Color = clWindowText TitleFont.Height = -11 TitleFont.Name = "Tahoma" TitleFont.Style = [] end object Button1: TButton Left = 303 Top = 24 Width = 110 Height = 25 Caption = "SQLite "#20869#32622#25490#24207 TabOrder = 1 OnClick = Button1Click end object Button2: TButton Left = 303 Top = 65 Width = 110 Height = 25 Caption = "FireDAC "#40664#35748#25490#24207 TabOrder = 2 OnClick = Button2Click end object FDConnection1: TFDConnection Left = 34 Top = 24 end object FDPhysSQLiteDriverLink1: TFDPhysSQLiteDriverLink Left = 143 Top = 24 end object FDGUIxWaitCursor1: TFDGUIxWaitCursor Provider = "Forms" Left = 260 Top = 24 end object FDQuery1: TFDQuery Connection = FDConnection1 Left = 32 Top = 88 end object DataSource1: TDataSource DataSet = FDQuery1 Left = 132 Top = 88 end object FDSQLiteCollation1: TFDSQLiteCollation DriverLink = FDPhysSQLiteDriverLink1 CollationName = "MyCollation" LocaleName = "zh-CN" Left = 240 Top = 120 end

代码:

procedure TForm1.FormCreate（Sender: TObject）;vari: Integer;LCode: Integer;begin{给 FDSQLiteCollation1 设定参数}FDSQLiteCollation1.DriverLink := FDPhysSQLiteDriverLink1;//  FDSQLiteCollation1.CollationKind := scCompareString; //这是默认值（Unicode 不区分大小写, 在 Win 下是调用 WinAPI.CompareString）; 使用其他选项需要自定义排序规则FDSQLiteCollation1.LocaleName := "zh-CN";FDSQLiteCollation1.Flags := [sfIgnoreCase];FDSQLiteCollation1.CollationName := "MyCollation"; //下面所有的调用全要依赖这个名称FDSQLiteCollation1.Active := True;FDConnection1.Params.Add（"DriverID=SQLite"）;//  FDConnection1.Params.Add（"OpenMode=CreateUTF8"）; //这是默认值, 可选 CreateUTF16（Unicode）{建立测试表, 三个字段 str（汉字）, code（汉字对应的 Unicode 值）, id（添加顺序）}FDConnection1.ExecSQL（"CREATE TABLE MyTable（str string（10）, code integer, id integer）"）;//  FDConnection1.ExecSQL（"CREATE TABLE MyTable（str string（10） COLLATE MyCollation, code integer, id integer）"）; //用在表设计时{添加测试数据数据}for i := 0to99dobeginLCode := Random（$9FA5-$4E00）;FDConnection1.ExecSQL（"INSERT INTO MyTable（str, code, id） VALUES（:1, :2, :3）", [WideChar（$4E00 + LCode）, LCode, i+1]）;end;FDQuery1.Open（"SELECT * FROM MyTable"）; //无排序end;procedure TForm1.Button1Click（Sender: TObject）;beginFDQuery1.Open（"SELECT * FROM MyTable ORDER BY str"）; //SQLite 内置排序end;procedure TForm1.Button2Click（Sender: TObject）;beginFDQuery1.Open（"SELECT * FROM MyTable ORDER BY str COLLATE MyCollation"）; //FireDAC 默认排序end;

测试效果图:

Author：cnblogs 万一