superobject 序列数据集
unit uDBJson;
interface
{$HINTS OFF}
uses
SysUtils, Classes, Variants, DB, DBClient, SuperObject;
type
TTableJSon = class
private 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 DataSetToJson(DataSet: TDataSet): ISuperObject;
class function DataSetToJson2(DataSet: TDataSet): string;
class function CreateFieldByJson(Fields: TFieldDefs;
ColsJson: ISuperObject): Boolean;
class procedure ImportDataFromJSon(DataSet: TDataSet;
DataJson: ISuperObject);
class function JSonToClientDataset(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;
implementation
uses TypInfo, encddecd;
{ TTableJSon }
class function TTableJSon.JSonToClientDataset(CDS: TClientDataSet;
Json: ISuperObject): Boolean;
var
ColsJson: ISuperObject;
begin
Result := False;
if Json = nil then
Exit;
CDS.Close;
CDS.Data := Null;
// 创建字段
ColsJson := Json.O[cstCols];
CreateFieldByJson(CDS.FieldDefs, ColsJson);
if CDS.FieldDefs.Count > 0 then
CDS.CreateDataSet;
ImportDataFromJSon(CDS, Json.O[cstData]);
Result := True;
end;
class function TTableJSon.CreateFieldByJson(Fields: TFieldDefs;
ColsJson: ISuperObject): Boolean;
var
SubJson: ISuperObject;
ft: TFieldType;
begin
Result := False;
Fields.DataSet.Close;
Fields.Clear;
for SubJson in ColsJson do
begin
ft := TFieldType(GetEnumValue(TypeInfo(TFieldType),
'ft' + SubJson.S[cstFieldType]));
if ft = ftAutoInc then // 自增字段不能录入,必须更改
ft := ftInteger;
Fields.Add(SubJson.S[cstFieldName], ft, SubJson.I[cstFieldSize],
SubJson.B[cstRequired]);
end;
Result := True;
end;
class function TTableJSon.CreateJsonValue(Json: ISuperObject;
const Name: string; const Value: Variant): Boolean;
begin
Result := False;
Json.O[Name] := SO(Value);
Result := True;
end;
class function TTableJSon.CreateJsonValueByField(Json: ISuperObject;
Field: TField): Boolean;
begin
Result := False;
if Field Is TDateTimeField then
Json.O[Field.FieldName] := SO(Field.AsDateTime)
else if Field is TBlobField then
Json.S[Field.FieldName] := EncodeString(Field.AsString)
else
Json.O[Field.FieldName] := SO(Field.Value);
Result := True;
end;
class function TTableJSon.GetValue(Json: ISuperObject;
const Name: string): Variant;
begin
case Json.DataType of
stNull:
Result := Null;
stBoolean:
Result := Json.B[Name];
stDouble:
Result := Json.D[Name];
stCurrency:
Result := Json.C[Name];
stInt:
Result := Json.I[Name];
stString:
Result := Json.S[Name];
end;
end;
class function TTableJSon.GetValue2Field(Field: TField;
JsonValue: ISuperObject): Variant;
begin
if JsonValue.DataType = stNull then
Result := Null
else if Field is TDateTimeField then
Result := JavaToDelphiDateTime(JsonValue.AsInteger)
else if (Field is TIntegerField) or (Field is TLargeintField) then
Result := JsonValue.AsInteger
else if Field is TNumericField then
Result := JsonValue.AsDouble
else if Field is TBooleanField then
Result := JsonValue.AsBoolean
else if Field is TStringField then
Result := JsonValue.AsString
else if Field is TBlobField then
Result := DecodeString(JsonValue.AsString)
end;
class procedure TTableJSon.ImportDataFromJSon(DataSet: TDataSet;
DataJson: ISuperObject);
var
SubJson: ISuperObject;
iter: TSuperObjectIter;
begin
if 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.DataSetToJson(DataSet: TDataSet): ISuperObject;
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;
var
sj, aj, sj2: ISuperObject;
I: Integer;
Fieldtyp, JsonTyp: string;
List: TStringList;
begin
sj := 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.Fields[I], Fieldtyp, JsonTyp);
sj2.S[cstFieldName] := DataSet.Fields[I].FieldName;
sj2.S[cstFieldType] := Fieldtyp;
sj2.S[cstJsonType] := JsonTyp;
sj2.I[cstFieldSize] := DataSet.Fields[I].Size;
sj2.B[cstRequired] := DataSet.Fields[I].Required;
sj2.I[cstFieldIndex] := DataSet.Fields[I].Index;
aj.AsArray.Add(sj2);
List.Add(DataSet.Fields[I].FieldName + '=' + JsonTyp);
end;
sj.O['Cols'] := 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
if VarIsNull(DataSet.Fields[I].Value) then
sj2.O[DataSet.Fields[I].FieldName] := SO(Null)
else
begin
CreateJsonValueByField(sj2, DataSet.Fields[I]);
end;
end;
aj.AsArray.Add(sj2);
DataSet.Next;
end;
sj.O['Data'] := aj;
Result := sj;
finally
List.Free;
DataSet.EnableControls;
end;
end;
class function TTableJSon.DataSetToJson2(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;
var
sj, aj, sj2: ISuperObject;
I: Integer;
Fieldtyp, JsonTyp: string;
List: TStringList;
begin
sj := 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.Fields[I], Fieldtyp, JsonTyp);
sj2.S[cstFieldName] := DataSet.Fields[I].FieldName;
sj2.S[cstFieldType] := Fieldtyp;
sj2.S[cstJsonType] := JsonTyp;
sj2.I[cstFieldSize] := DataSet.Fields[I].Size;
sj2.B[cstRequired] := DataSet.Fields[I].Required;
sj2.I[cstFieldIndex] := DataSet.Fields[I].Index;
aj.AsArray.Add(sj2);
List.Add(DataSet.Fields[I].FieldName + '=' + JsonTyp);
end;
sj.O['Cols'] := 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
if VarIsNull(DataSet.Fields[I].Value) then
sj2.O[DataSet.Fields[I].FieldName] := SO(Null)
else
begin
CreateJsonValueByField(sj2, DataSet.Fields[I]);
end;
end;
aj.AsArray.Add(sj2);
DataSet.Next;
end;
sj.O['Data'] := aj;
Result := sj.AsString;
finally
List.Free;
DataSet.EnableControls;
end;
end;
end.
本文来自博客园,作者:{咏南中间件},转载请注明原文链接:https://www.cnblogs.com/hnxxcxg/archive/2012/05/22/2512948.html