Delphi中JSon_SuperObject_使用数据集与JSON对象互转.doc

在delphi中，数据集是最常用数据存取方式。因此，必须建立JSON与TDataSet之间的互转关系，实现数据之间通讯与转换。值得注意的是，这只是普通的TDataset与JSON之间转换，由于CDS包含了Delta数据包，其数据格式远比普通的TDataset更复杂。 数据集字段信息，是一个完整的字典信息。因此，我们在JSON必须也建立字典信息，才能创建数据集的字段信息。我们设置其JSON信息如下： COLS:字段列表信息，如：Cols:JsonType:integer,FieldIndex:0,FieldType:Integer,FieldSize:0,FieldName:ID,Required:false,JsonType:string,FieldIndex:1,FieldType:String,FieldSize:100,FieldName:Title,Required:false,JsonType:variant,FieldIndex:2,FieldType:Blob,FieldSize:0,FieldName:Picture,Required:false数据信息以Data做节点，也是一个数组嵌套记录信息：Data:记录集信息废话少说，直接上代码：unit uDBJson;interfaceusesSysUtils,Classes,Variants,DB,DBClient,SuperObject;typeTTableJSon = classprivate const cstFieldType = FieldType; const cstFieldName = FieldName; const cstFieldSize = FieldSize; const cstJsonType = JsonType; const cstRequired = Required; const cstFieldIndex = FieldIndex; const cstCols= Cols; const cstData= Data;public class function JSonFromDataSet(DataSet:TDataSet):string; class function CreateFieldByJson(Fields:TFieldDefs;ColsJson:ISuperObject):Boolean; class function ImportDataFromJSon(DataSet:TDataSet;DataJson:ISuperObject):Integer; class function CDSFromJSon(CDS:TClientDataSet;Json:ISuperObject):Boolean; class function GetValue(Json:ISuperObject;const Name:string):Variant; class function CreateJsonValue(Json:ISuperObject;const Name:string;const Value:Variant):Boolean; class function CreateJsonValueByField(Json:ISuperObject;Field:TField):Boolean; class function GetValue2Field(Field:TField;JsonValue:ISuperObject):Variant;end;implementationuses TypInfo,encddecd; TTableJSon class function TTableJSon.CDSFromJSon(CDS: TClientDataSet;Json: ISuperObject): Boolean;varColsJson:ISuperObject; beginResult := False;if Json = nil then Exit;CDS.Close;CDS.Data := Null;/创建字段ColsJson := Json.OcstCols;CreateFieldByJson(CDS.FieldDefs,ColsJson);if CDS.FieldDefs.Count 0 then CDS.CreateDataSet;ImportDataFromJSon(CDS,Json.OcstData);Result := True;end;class function TTableJSon.CreateFieldByJson(Fields: TFieldDefs;ColsJson: ISuperObject): Boolean;varSubJson:ISuperObject;ft:TFieldType;beginResult := False;Fields.DataSet.Close;Fields.Clear;for SubJson in ColsJson dobegin ft := TFieldType(GetEnumValue(TypeInfo(TFieldType),ft+SubJson.ScstFieldType); if ft= ftAutoInc then /自增字段不能录入，必须更改 ft := ftInteger; Fields.Add(SubJson.ScstFieldName,ft,SubJson.IcstFieldSize,SubJson.BcstRequired);end;Result := True;end;class function TTableJSon.CreateJsonValue(Json: ISuperObject;const Name: string; const Value: Variant): Boolean;beginResult := False;Json.OName := SO(Value);Result := True;end;class function TTableJSon.CreateJsonValueByField(Json: ISuperObject;Field: TField): Boolean;beginResult := False;if Field Is TDateTimeField then Json.OField.FieldName := SO(Field.AsDateTime)else if Field is TBlobField then Json.SField.FieldName := EncodeString(Field.AsString)else Json.OField.FieldName := SO(Field.Value);Result := True;end;class function TTableJSon.GetValue(Json: ISuperObject;const Name: string): Variant;begincase Json.DataType of stNull: Result := Null; stBoolean: Result := Json.BName; stDouble: Result := Json.DName; stCurrency: Result := Json.CName; stInt: Result := Json.IName; stString: Result := Json.SName;end;end;class function TTableJSon.GetValue2Field(Field: TField; JsonValue:ISuperObject): Variant;beginif JsonValue.DataType = stNull then Result := Nullelse if Field is TDateTimeField then Result := JavaToDelphiDateTime(JsonValue.AsInteger)else if (Field is TIntegerField) or (Field is TLargeintField) then Result := JsonValue.AsIntegerelse if Field is TNumericField then Result := JsonValue.AsDoubleelse if Field is TBooleanField then Result := JsonValue.AsBooleanelse if Field is TStringField then Result := JsonValue.AsStringelse if Field is TBlobField then Result := DecodeString(JsonValue.AsString) end;class function TTableJSon.ImportDataFromJSon(DataSet: TDataSet;DataJson: ISuperObject): Integer;varSubJson:ISuperObject;i:Integer;iter: TSuperObjectIter;beginif not DataSet.Active then DataSet.Open;DataSet.DisableControls;try for SubJson in DataJson do begin DataSet.Append; if ObjectFindFirst(SubJson,iter) then begin repeat if DataSet.FindField(iter.Ite.Current.Name)nil then DataSet.FindField(iter.Ite.Current.Name).Value := GetValue2Field( DataSet.FindField(iter.Ite.Current.Name), iter.Ite.Current.Value); until not ObjectFindNext(iter) ; end; DataSet.Post; end;finally DataSet.EnableControls;end; end;class function TTableJSon.JSonFromDataSet(DataSet:TDataSet):string;procedure GetFieldTypeInfo(Field:TField;var Fieldtyp,JsonTyp:string);begin Fieldtyp := GetEnumName(TypeInfo(tfieldtype),ord(Field.DataType); Delete(Fieldtyp,1,2); if Field is TStringField then JsonTyp := string else if Field is TDateTimeField then JsonTyp := integer else if (Field is TIntegerField) or (Field is TLargeintField) then JsonTyp := integer else if Field is TCurrencyField then JsonTyp := currency else if Field is TNumericField then JsonTyp := double else if Field is TBooleanField then JsonTyp := boolean else JsonTyp := variant;end;varsj,aj,sj2:ISuperObject;i:Integer;Fieldtyp,JsonTyp:string;List:TStringList;beginsj := SO();/创建列aj := SA();List := TStringList.Create;try List.Sorted := True; for i := 0 to DataSet.FieldCount - 1 do begin sj2 := SO(); GetFieldTypeInfo(DataSet.Fieldsi,Fieldtyp,JsonTyp); sj2.ScstFieldName := DataSet.Fieldsi.FieldName; sj2.ScstFieldType := Fieldtyp; sj2.ScstJsonType := JsonTyp; sj2.IcstFieldSize := DataSet.Fieldsi.Size; sj2.BcstRequired := DataSet.Fieldsi.Required; sj2.IcstFieldIndex := DataSet.Fieldsi.Index; aj.AsArray.Add(sj2); List.Add(DataSet.Fieldsi.FieldName+=+JsonTyp); end; sj.OCols := aj; /创建数据集的数据 DataSet.DisableControls; DataSet.First; aj := SA(); while not DataSet.Eof do begin sj2 := SO(); for i := 0 to DataSet.FieldCount - 1 do begin /sj2.SIntToStr(DataSet.Fieldsi.Index) := VarToStrDef(DataSet.Fieldsi.Value,); if VarIsNull(DataSet.Fieldsi.Value) then sj2.ODataSet.Fieldsi.FieldName := SO(Null) else begin CreateJsonValueByField(sj2,DataSet.Fieldsi); end; end; aj.AsArray.Add(sj2); DataSet.Next; end; sj.OData := aj; Result := sj.AsString;finally List.Free; DataSet.EnableControls;end;end;end.调用示例：/数据集转JSON对象或JSON文本varjson:TTableJSon;s:string;beginS := json.JSonFromDataSet(ADODataSet1);/在用TStringStream读入字符串S，存成文本，看看其格式.end;/JSON对象或文本，装载到数据集varjson:ISuperObject;beginjson := TSuperObject.ParseFile(json.txt,False);TTableJSon.CDSFromJSon(cdsJSON,json);end; JSON不能完全替代XML，但绝对是未来的大势所趋，其优点是简单、体积小、解析更快、解析占用资源更少。在delphi中，数据集是最常用数据存取方式。因此，必须建立JSON与TDataSet之间的互转关系，实现数据之间通讯与转换。值得注意的是，这只是普通的TDataset与JSON之间转换，由于CDS包含了Delta数据包，其数据格式远比普通的TDataset更复杂。下面的程序，或许你有不同的想法，如果你的想法更好更快，欢迎一起讨论。今天是2009年最后的几十分钟，重要的并不是写博客，而是想向大家说一声“新年好运，事业有成”！ 数据集字段信息，是一个完整的字典信息。因此，我们在JSON必须也建立字典信息，才能创建数据集的字段信息。我们设置其JSON信息如下： COLS:字段列表信息，如：Cols:JsonType:integer,FieldIndex:0,FieldType:Integer,FieldSize:0,FieldName:ID,Required:false,JsonType:string,FieldIndex:1,FieldType:String,FieldSize:100,FieldName:Title,Required:false,JsonType:variant,FieldIndex:2,FieldType:Blob,FieldSize:0,FieldName:Picture,Required:false数据信息以Data做节点，也是一个数组嵌套记录信息：Data:记录集信息废话少说，直接上代码：unit uDBJson;interfaceusesSysUtils,Classes,Variants,DB,DBClient,SuperObject;typeTTableJSon = classprivate const cstFieldType = FieldType; const cstFieldName = FieldName; const cstFieldSize = FieldSize; const cstJsonType = JsonType; const cstRequired = Required; const cstFieldIndex = FieldIndex; const cstCols= Cols; const cstData= Data;public class function JSonFromDataSet(DataSet:TDataSet):string; class function CreateFieldByJson(Fields:TFieldDefs;ColsJson:ISuperObject):Boolean; class function ImportDataFromJSon(DataSet:TDataSet;DataJson:ISuperObject):Integer; class function CDSFromJSon(CDS:TClientDataSet;Json:ISuperObject):Boolean; class function GetValue(Json:ISuperObject;const Name:string):Variant; class function CreateJsonValue(Json:ISuperObject;const Name:string;const Value:Variant):Boolean; class function CreateJsonValueByField(Json:ISuperObject;Field:TField):Boolean; class function GetValue2Field(Field:TField;JsonValue:ISuperObject):Variant;end;implementationuses TypInfo,encddecd; TTableJSon class function TTableJSon.CDSFromJSon(CDS: TClientDataSet;Json: ISuperObject): Boolean;varColsJson:ISuperObject; beginResult := False;if Json = nil then Exit;CDS.Close;CDS.Data := Null;/创建字段ColsJson := Json.OcstCols;CreateFieldByJson(CDS.FieldDefs,ColsJson);if CDS.FieldDefs.Count 0 then CDS.CreateDataSet;ImportDataFromJSon(CDS,Json.OcstData);Result := True;end;class function TTableJSon.CreateFieldByJson(Fields: TFieldDefs;ColsJson: ISuperObject): Boolean;varSubJson:ISuperObject;ft:TFieldType;beginResult := False;Fields.DataSet.Close;Fields.Clear;for SubJson in ColsJson dobegin ft := TFieldType(GetEnumValue(TypeInfo(TFieldType),ft+SubJson.ScstFieldType); if ft= ftAutoInc then /自增字段不能录入，必须更改 ft := ftInteger; Fields.Add(SubJson.ScstFieldName,ft,SubJson.IcstFieldSize,SubJson.BcstRequired);end;Result := True;end;class function TTableJSon.CreateJsonValue(Json: ISuperObject;const Name: string; const Value: Variant): Boolean;beginResult := False;Json.OName := SO(Value);Result := True;end;class function TTableJSon.CreateJsonValueByField(Json: ISuperObject;Field: TField): Boolean;beginResult := False;if Field Is TDateTimeField then Json.OField.FieldName := SO(Field.AsDateTime)else if Field is TBlobField then Json.SField.FieldName := EncodeString(Field.AsString)else Json.OField.FieldName := SO(Field.Value);Result := True;end;class function TTableJSon.GetValue(Json: ISuperObject;const Name: string): Variant;begincase Json.DataType of stNull: Result := Null; stBoolean: Result := Json.BName; stDouble: Result := Json.DName; stCurrency: Result := Json.CName; stInt: Result := Json.IName; stString: Result := Json.SName;end;end;class function TTableJSon.GetValue2Field(Field: TField; JsonValue:ISuperObject): Variant;beginif JsonValue.DataType = stNull then Result := Nullelse if Field is TDateTimeField then Result := JavaToDelphiDateTime(JsonValue.AsInteger)else if (Field is TIntegerField) or (Field is TLargeintField) then Result := JsonValue.AsIntegerelse if Field is TNumericField then Result := JsonValue.AsDoubleelse if Field is TBooleanField then Result := JsonValue.AsBooleanelse if Field is TStringField then Result := JsonValue.AsStringelse if Field is TBlobField then Result := DecodeString(JsonValue.AsString) end;class function TTableJSon.ImportDataFromJSon(DataSet: TDataSet;DataJson: ISuperObject): Integer;varSubJson:ISuperObject;i:Integer;iter: TSuperObjectIter;beginif not DataSet.Active then DataSet.Open;DataSet.DisableControls;try for SubJson in DataJson do begin DataSet.Append; if ObjectFindFirst(SubJson,iter) then begin repeat if DataSet.FindField(iter.Ite.Current.Name)nil then DataSet.FindField(iter.Ite.Current.Name).Value := GetValue2Field( DataSet.FindField(iter.Ite.Current.Name), iter.Ite.Current.Value); until not ObjectFindNext(iter) ; end; DataSet.Post; end;finally DataSet.EnableControls;end; end;class function TTableJSon.JSonFromDataSet(DataSet:TDataSet):string;procedure GetFieldTypeInfo(Field:TField;var Fieldtyp,JsonTyp:string);begin Fieldtyp := GetEnumName(TypeInfo(tfieldtype),ord(Field.DataType); Delete(Fieldtyp,1,2); if Field is TStringField then JsonTyp := string else if Field is TDateTimeField then JsonTyp := integer else if (Field is TIntegerField) or (Field is TLargeintField) then JsonTyp := integer else if Field is TCurrencyField then JsonTyp := currency else if Field is TNumericField then JsonTyp := double else if Field is TBooleanField then JsonTyp := boolean else JsonTyp := variant;end;varsj,aj,sj2:ISuperObject;i:Integer;Fieldtyp,JsonTyp:string;List:TStringList;beginsj := SO();/创建列aj := SA();List := TStringList.Create;try List.Sorted := True; for i := 0 to DataSet.FieldCount - 1 do begin sj2 := SO(); GetFieldTypeInfo(DataSet.Fieldsi,Fieldtyp,JsonTyp); sj2.ScstFieldName := DataSet.Fieldsi.FieldName; sj2.ScstFieldType := Fieldtyp; sj2.ScstJsonType := JsonTyp; sj2.IcstFieldSize := DataSet.Fieldsi.Size; sj2.BcstRequired := DataSet.Fieldsi.Required; sj2.IcstFieldIndex := DataSet.Fieldsi.Index; aj.AsArray.Add(sj2); List.Add(DataSet.Fieldsi.FieldName+=+JsonTyp); end; sj.OCols := aj; /创建数据集的数据 DataSet.DisableControls; DataSet.First; aj := SA(); while not DataSet.Eof do begin sj2 := SO(); for i := 0 to DataSet.FieldCount - 1 do begin /sj2.SIntToStr(DataSet.Fieldsi.Index) := VarToStrDef(DataSet.Fieldsi.Value,); if VarIsNull(DataSet.Fieldsi.Value) then sj2.ODataSet.Fieldsi.FieldName := SO(Null) else begin CreateJsonValueByField(sj2,DataSet.Fieldsi); end; end; aj.AsArray.Add(sj2); DataSet.Next; end; sj.OData := aj; Result := sj.AsString;finally List.Free; DataSet.EnableControls;end; end;end.调用示例：/数据集转JSON对象或JSON文本varjson:TTableJSon;s:string;beginS := json.JSonFromDataSet(ADODataSet1);/在用TStringStream读入字符串S，存成文本，看看其格式.end;/JSON对象或文本，装载到数据集varjson:ISuperObject;beginjson := TSuperObject.ParseFile(json.txt,False);TTableJSon.CDSFromJSon(cdsJSON,json);end; JSON不能完全替代XML，但绝对是未来的大势所趋，其优点是简单、体积小、解析更快、解析占用资源更少。在delphi中，数据集是最常用数据存取方式。因此，必须建立JSON与TDataSet之间的互转关系，实现数据之间通讯与转换。值得注意的是，这只是普通的TDataset与JSON之间转换，由于CDS包含了Delta数据包，其数据格式远比普通的TDataset更复杂。下面的程序，或许你有不同的想法，如果你的想法更好更快，欢迎一起讨论。今天是2009年最后的几十分钟，重要的并不是写博客，而是想向大家说一声“新年好运，事业有成”！ 数据集字段信息，是一个完整的字典信息。因此，我们在JSON必须也建立字典信息，才能创建数据集的字段信息。我们设置其JSON信息如下： COLS:字段列表信息，如：Cols:JsonType:integer,FieldIndex:0,FieldType:Integer,FieldSize:0,FieldName:ID,Required:false,JsonType:string,FieldIndex:1,FieldType:String,FieldSize:100,FieldName:Title,Required:false,JsonType:variant,FieldIndex:2,FieldType:Blob,FieldSize:0,FieldName:Picture,Required:false数据信息以Data做节点，也是一个数组嵌套记录信息：Data:记录集信息废话少说，直接上代码：unit uDBJson;interfaceusesSysUtils,Classes,Variants,DB,DBClient,SuperObject;typeTTableJSon = classprivate const cstFieldType = FieldType; const cstFieldName = FieldName; const cstFieldSize = FieldSize; const cstJsonType = JsonType; const cstRequired = Required; const cstFieldIndex = FieldIndex; const cstCols= Cols; const cstData= Data;public class function JSonFromDataSet(DataSet:TDataSet):string; class function CreateFieldByJson(Fields:TFieldDefs;ColsJson:ISuperObject):Boolean; class function ImportDataFromJSon(DataSet:TDataSet;DataJson:ISuperObject):Integer; class function CDSFromJSon(CDS:TClientDataSet;Json:ISuperObject):Boolean; class function GetValue(Json:ISuperObject;const Name:string):Variant; class function CreateJsonValue(Json:ISuperObject;const Name:string;const Value:Variant):Boolean; class function CreateJsonValueByField(Json:ISuperObject;Field:TField):Boolean; class function GetValue2Field(Field:TField;JsonValue:ISuperObject):Variant;end;implementationuses TypInfo,encddecd; TTableJSon class function TTableJSon.CDSFromJSon(CDS: TClientDataSet;Json: ISuperObject): Boolean;varColsJson:ISuperObject; beginResult := False;if Json = nil then Exit;CDS.Close;CDS.Data := Null;/创建字段ColsJson := Json.OcstCols;CreateFieldByJson(CDS.FieldDefs,ColsJson);if CDS.FieldDefs.Count 0 then CDS.CreateDataSet;ImportDataFromJSon(CDS,Json.OcstData);Result := True;end;class function TTableJSon.CreateFieldByJson(Fields: TFieldDefs;ColsJson: ISuperObject): Boolean;varSubJson:ISuperObject;ft:TFieldType;beginResult := False;Fields.DataSet.Close;Fields.Clear;for SubJson in ColsJson dobegin ft := TFieldType(GetEnumValue(TypeInfo(TFieldType),ft+SubJson.ScstFieldType); if ft= ftAutoInc then /自增字段不能录入，必须更改 ft := ftInteger; Fields.Add(SubJson.ScstFieldName,ft,SubJson.IcstFieldSize,SubJson.BcstR