delphimvcframework/sources/MVCFramework.Rtti.Utils.pas
2022-07-25 15:42:37 +02:00

931 lines
27 KiB
ObjectPascal

// ***************************************************************************
//
// Delphi MVC Framework
//
// Copyright (c) 2010-2022 Daniele Teti and the DMVCFramework Team
//
// https://github.com/danieleteti/delphimvcframework
//
// ***************************************************************************
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// ***************************************************************************
unit MVCFramework.Rtti.Utils;
{$I dmvcframework.inc}
interface
uses
System.Classes,
System.TypInfo,
System.Rtti,
System.Generics.Collections,
System.SysUtils,
Data.DB;
type
TRttiUtils = class sealed
private
class constructor Create;
class destructor Destroy;
public
class var GlContext: TRttiContext;
public
class function GetMethod(AObject: TObject; AMethodName: string): TRttiMethod;
class function GetField(AObject: TObject; const APropertyName: string): TValue; overload;
class function GetFieldType(AProp: TRttiProperty): string;
class procedure SetField(AObject: TObject; const APropertyName: string; const AValue: TValue); overload;
class function GetPropertyType(AObject: TObject; APropertyName: string): string;
class function GetProperty(AObject: TObject; const APropertyName: string): TValue;
// class function GetPropertyAsString(AObject: TObject; const APropertyName: string): string; overload;
// class function GetPropertyAsString(AObject: TObject; AProperty: TRttiProperty): string; overload;
class function ExistsProperty(AObject: TObject; const APropertyName: string; out AProperty: TRttiProperty): Boolean;
class procedure SetProperty(AObject: TObject; const APropertyName: string; const AValue: TValue); overload; static;
class function MethodCall(AObject: TObject; AMethodName: string; AParameters: array of TValue;
ARaiseExceptionIfNotFound: Boolean = true): TValue;
class procedure ObjectToDataSet(AObject: TObject; AField: TField; var AValue: Variant);
class procedure DatasetToObject(ADataset: TDataset; AObject: TObject);
class function Clone(AObject: TObject): TObject; static;
class procedure CopyObject(ASourceObject, ATargetObject: TObject); static;
class procedure CopyObjectAS<T: class>(ASourceObject, ATargetObject: TObject); static;
class function CreateObject(ARttiType: TRttiType; const AParams: TArray<TValue> = nil): TObject; overload; static;
class function CreateObject(AQualifiedClassName: string; const AParams: TArray<TValue> = nil): TObject;
overload; static;
class function GetAttribute<T: TCustomAttribute>(const AObject: TRttiObject): T; overload;
class function GetAttribute<T: TCustomAttribute>(const AObject: TRttiType): T; overload;
class function HasAttribute<T: TCustomAttribute>(const AObject: TRttiObject): Boolean; overload;
class function HasAttribute<T: TCustomAttribute>(const AObject: TRttiObject; out AAttribute: T): Boolean; overload;
class function HasAttribute<T: class>(AObject: TObject; out AAttribute: T): Boolean; overload;
class function HasAttribute<T: class>(ARttiMember: TRttiMember; out AAttribute: T): Boolean; overload;
class function HasAttribute<T: class>(ARttiMember: TRttiType; out AAttribute: T): Boolean; overload;
class function TValueAsString(const AValue: TValue; const APropertyType, ACustomFormat: string): string;
class function EqualValues(ASource, ADestination: TValue): Boolean;
class function FindByProperty<T: class>(AList: TObjectList<T>; APropertyName: string; APropertyValue: TValue): T;
class procedure ForEachProperty(AClazz: TClass; AProc: TProc<TRttiProperty>);
// class function HasStringValueAttribute<T: class>(ARttiMember: TRttiMember; out AValue: string): Boolean;
class function BuildClass(AQualifiedName: string; AParams: array of TValue): TObject;
class function FindType(AQualifiedName: string): TRttiType;
class function GetGUID<T>: TGUID;
class function GetArrayContainedRTTIType(const RTTIType: TRttiType): TRttiType;
end;
{$IF not defined(BERLINORBETTER)}
TValueHelper = record helper for TValue
public
function IsObjectInstance: Boolean;
end;
{$ENDIF}
function FieldFor(const APropertyName: string): string; inline;
implementation
uses
MVCFramework.DuckTyping,
MVCFramework.Serializer.Commons;
class function TRttiUtils.MethodCall(AObject: TObject; AMethodName: string; AParameters: array of TValue;
ARaiseExceptionIfNotFound: Boolean): TValue;
var
m: TRttiMethod;
T: TRttiType;
Found: Boolean;
ParLen: Integer;
MethodParamsLen: Integer;
begin
Found := False;
T := GlContext.GetType(AObject.ClassInfo);
ParLen := Length(AParameters);
m := nil;
for m in T.GetMethods do
begin
MethodParamsLen := Length(m.GetParameters);
if m.Name.Equals(AMethodName) and (MethodParamsLen = ParLen) then
begin
Found := true;
Break;
end;
end;
if Found then
Result := m.Invoke(AObject, AParameters)
else if ARaiseExceptionIfNotFound then
raise Exception.CreateFmt('Cannot find compatible method "%s" in the object', [AMethodName]);
end;
function FieldFor(const APropertyName: string): string; inline;
begin
Result := 'F' + APropertyName;
end;
class function TRttiUtils.GetAttribute<T>(const AObject: TRttiObject): T;
var
Attr: TCustomAttribute;
begin
Result := nil;
for Attr in AObject.GetAttributes do
begin
if Attr.ClassType.InheritsFrom(T) then
Exit(T(Attr));
end;
end;
class function TRttiUtils.GetArrayContainedRTTIType(
const RTTIType: TRttiType): TRttiType;
var
lName: string;
begin
lName := RTTIType.Name;
if not lName.StartsWith('TArray<') then
begin
raise EMVCDeserializationException.CreateFmt('%s is not an array', [lName]);
end;
lName := lName.Remove(0, 7);
lName := lName.Remove(lName.Length - 1);
Result := GlContext.FindType(lName);
end;
class function TRttiUtils.GetAttribute<T>(const AObject: TRttiType): T;
var
Attr: TCustomAttribute;
begin
Result := nil;
for Attr in AObject.GetAttributes do
begin
if Attr.ClassType.InheritsFrom(T) then
Exit(T(Attr));
end;
end;
class function TRttiUtils.GetField(AObject: TObject; const APropertyName: string): TValue;
var
Field: TRttiField;
Prop: TRttiProperty;
ARttiType: TRttiType;
begin
ARttiType := GlContext.GetType(AObject.ClassType);
if not Assigned(ARttiType) then
raise Exception.CreateFmt('Cannot get RTTI for type [%s]', [ARttiType.ToString]);
Field := ARttiType.GetField(FieldFor(APropertyName));
if Assigned(Field) then
Result := Field.GetValue(AObject)
else
begin
Prop := ARttiType.GetProperty(APropertyName);
if not Assigned(Prop) then
raise Exception.CreateFmt('Cannot get RTTI for property [%s.%s]', [ARttiType.ToString, APropertyName]);
Result := Prop.GetValue(AObject);
end;
end;
class function TRttiUtils.GetProperty(AObject: TObject; const APropertyName: string): TValue;
var
Prop: TRttiProperty;
ARttiType: TRttiType;
begin
ARttiType := GlContext.GetType(AObject.ClassType);
if not Assigned(ARttiType) then
raise Exception.CreateFmt('Cannot get RTTI for type [%s]', [ARttiType.ToString]);
Prop := ARttiType.GetProperty(APropertyName);
if not Assigned(Prop) then
raise Exception.CreateFmt('Cannot get RTTI for property [%s.%s]', [ARttiType.ToString, APropertyName]);
if Prop.IsReadable then
Result := Prop.GetValue(AObject)
else
raise Exception.CreateFmt('Property is not readable [%s.%s]', [ARttiType.ToString, APropertyName]);
end;
// class function TRttiUtils.GetPropertyAsString(AObject: TObject; AProperty: TRttiProperty): string;
// var
// P: TValue;
// FT: string;
// CustomFormat: string;
// begin
// if AProperty.IsReadable then
// begin
// P := AProperty.GetValue(AObject);
// FT := GetFieldType(AProperty);
// HasStringValueAttribute<StringValueAttribute>(AProperty, CustomFormat);
// Result := TValueAsString(P, FT, CustomFormat);
// end
// else
// Result := '';
// end;
//
// class function TRttiUtils.GetPropertyAsString(AObject: TObject; const APropertyName: string): string;
// var
// Prop: TRttiProperty;
// begin
// Prop := GlContext.GetType(AObject.ClassType).GetProperty(APropertyName);
// if Assigned(Prop) then
// Result := GetPropertyAsString(AObject, Prop)
// else
// Result := '';
// end;
class function TRttiUtils.GetPropertyType(AObject: TObject; APropertyName: string): string;
begin
Result := GetFieldType(GlContext.GetType(AObject.ClassInfo).GetProperty(APropertyName));
end;
class function TRttiUtils.HasAttribute<T>(const AObject: TRttiObject): Boolean;
begin
Result := Assigned(GetAttribute<T>(AObject));
end;
class function TRttiUtils.HasAttribute<T>(ARttiMember: TRttiMember; out AAttribute: T): Boolean;
var
attrs: TArray<TCustomAttribute>;
Attr: TCustomAttribute;
begin
AAttribute := nil;
Result := False;
attrs := ARttiMember.GetAttributes;
for Attr in attrs do
if Attr is T then
begin
AAttribute := T(Attr);
Exit(true);
end;
end;
class function TRttiUtils.HasAttribute<T>(ARttiMember: TRttiType; out AAttribute: T): Boolean;
var
attrs: TArray<TCustomAttribute>;
Attr: TCustomAttribute;
begin
AAttribute := nil;
Result := False;
attrs := ARttiMember.GetAttributes;
for Attr in attrs do
if Attr is T then
begin
AAttribute := T(Attr);
Exit(true);
end;
end;
class function TRttiUtils.HasAttribute<T>(const AObject: TRttiObject; out AAttribute: T): Boolean;
begin
AAttribute := GetAttribute<T>(AObject);
Result := Assigned(AAttribute);
end;
// class function TRttiUtils.HasStringValueAttribute<T>(ARttiMember: TRttiMember; out AValue: string): Boolean;
// var
// Attr: T; // StringValueAttribute;
// begin
// Result := HasAttribute<T>(ARTTIMember, Attr);
// if Result then
// AValue := StringValueAttribute(Attr).Value
// else
// AValue := '';
// end;
class procedure TRttiUtils.SetField(AObject: TObject; const APropertyName: string; const AValue: TValue);
var
Field: TRttiField;
Prop: TRttiProperty;
ARttiType: TRttiType;
begin
ARttiType := GlContext.GetType(AObject.ClassType);
if not Assigned(ARttiType) then
raise Exception.CreateFmt('Cannot get RTTI for type [%s]', [ARttiType.ToString]);
Field := ARttiType.GetField(FieldFor(APropertyName));
if Assigned(Field) then
Field.SetValue(AObject, AValue)
else
begin
Prop := ARttiType.GetProperty(APropertyName);
if Assigned(Prop) then
begin
if Prop.IsWritable then
Prop.SetValue(AObject, AValue)
end
else
raise Exception.CreateFmt('Cannot get RTTI for field or property [%s.%s]', [ARttiType.ToString, APropertyName]);
end;
end;
class procedure TRttiUtils.SetProperty(AObject: TObject; const APropertyName: string; const AValue: TValue);
var
Prop: TRttiProperty;
ARttiType: TRttiType;
begin
ARttiType := GlContext.GetType(AObject.ClassType);
if not Assigned(ARttiType) then
raise Exception.CreateFmt('Cannot get RTTI for type [%s]', [ARttiType.ToString]);
Prop := ARttiType.GetProperty(APropertyName);
if not Assigned(Prop) then
raise Exception.CreateFmt('Cannot get RTTI for property [%s.%s]', [ARttiType.ToString, APropertyName]);
if Prop.IsWritable then
Prop.SetValue(AObject, AValue)
else
raise Exception.CreateFmt('Property is not writeable [%s.%s]', [ARttiType.ToString, APropertyName]);
end;
class function TRttiUtils.TValueAsString(const AValue: TValue; const APropertyType, ACustomFormat: string): string;
begin
case AValue.Kind of
tkUnknown:
Result := '';
tkInteger:
Result := IntToStr(AValue.AsInteger);
tkChar:
Result := AValue.AsString;
tkEnumeration:
if APropertyType = 'boolean' then
Result := BoolToStr(AValue.AsBoolean, true)
else
Result := '(enumeration)';
tkFloat:
begin
if APropertyType = 'datetime' then
begin
if ACustomFormat = '' then
Exit(DateTimeToStr(AValue.AsExtended))
else
Exit(FormatDateTime(ACustomFormat, AValue.AsExtended))
end
else if APropertyType = 'date' then
begin
if ACustomFormat = '' then
Exit(DateToStr(AValue.AsExtended))
else
Exit(FormatDateTime(ACustomFormat, Trunc(AValue.AsExtended)))
end
else if APropertyType = 'time' then
begin
if ACustomFormat = '' then
Exit(TimeToStr(AValue.AsExtended))
else
Exit(FormatDateTime(ACustomFormat, Frac(AValue.AsExtended)))
end;
if ACustomFormat.IsEmpty then
Result := FloatToStr(AValue.AsExtended)
else
Result := FormatFloat(ACustomFormat, AValue.AsExtended);
end;
tkString:
Result := AValue.AsString;
tkSet:
Result := '';
tkClass:
Result := AValue.AsObject.QualifiedClassName;
tkMethod:
Result := '';
tkWChar:
Result := AValue.AsString;
tkLString:
Result := AValue.AsString;
tkWString:
Result := AValue.AsString;
tkVariant:
Result := string(AValue.AsVariant);
tkArray:
Result := '(array)';
tkRecord:
Result := '(record)';
tkInterface:
Result := '(interface)';
tkInt64:
Result := IntToStr(AValue.AsInt64);
tkDynArray:
Result := '(array)';
tkUString:
Result := AValue.AsString;
tkClassRef:
Result := '(classref)';
tkPointer:
Result := '(pointer)';
tkProcedure:
Result := '(procedure)';
else
Result := '';
end;
end;
class function TRttiUtils.GetFieldType(AProp: TRttiProperty): string;
var
_PropInfo: PTypeInfo;
begin
_PropInfo := AProp.PropertyType.Handle;
if _PropInfo.Kind in [tkString, tkWString, tkChar, tkWChar, tkLString, tkUString] then
Result := 'string'
else if _PropInfo.Kind in [tkInteger, tkInt64] then
Result := 'integer'
else if _PropInfo = TypeInfo(TDate) then
Result := 'date'
else if _PropInfo = TypeInfo(TDateTime) then
Result := 'datetime'
else if _PropInfo = TypeInfo(Currency) then
Result := 'decimal'
else if _PropInfo = TypeInfo(TTime) then
begin
Result := 'time'
end
else if _PropInfo.Kind = tkFloat then
begin
Result := 'float'
end
else if (_PropInfo.Kind = tkEnumeration) { and (_PropInfo.Name = 'Boolean') } then
Result := 'boolean'
else if AProp.PropertyType.IsInstance and AProp.PropertyType.AsInstance.MetaclassType.InheritsFrom(TStream) then
Result := 'blob'
else
Result := EmptyStr;
end;
class function TRttiUtils.GetGUID<T>: TGUID;
var
Tp: TRttiType;
begin
Tp := GlContext.GetType(TypeInfo(T));
if not(Tp.TypeKind = tkInterface) then
raise Exception.Create('Type is no interface');
Result := TRttiInterfaceType(Tp).GUID;
end;
class function TRttiUtils.GetMethod(AObject: TObject; AMethodName: string): TRttiMethod;
var
T: TRttiType;
begin
T := GlContext.GetType(AObject.ClassInfo);
Result := T.GetMethod(AMethodName);
end;
class procedure TRttiUtils.ObjectToDataSet(AObject: TObject; AField: TField; var AValue: Variant);
begin
AValue := GetProperty(AObject, AField.FieldName).AsVariant;
end;
class procedure TRttiUtils.DatasetToObject(ADataset: TDataset; AObject: TObject);
var
ARttiType: TRttiType;
props: TArray<TRttiProperty>;
Prop: TRttiProperty;
f: TField;
begin
ARttiType := GlContext.GetType(AObject.ClassType);
props := ARttiType.GetProperties;
for Prop in props do
if not SameText(Prop.Name, 'ID') then
begin
f := ADataset.FindField(Prop.Name);
if Assigned(f) and not f.ReadOnly then
begin
if f is TIntegerField then
SetProperty(AObject, Prop.Name, TIntegerField(f).Value)
else
SetProperty(AObject, Prop.Name, TValue.From<Variant>(f.Value))
end;
end;
end;
class destructor TRttiUtils.Destroy;
begin
GlContext.Free;
end;
class function TRttiUtils.EqualValues(ASource, ADestination: TValue): Boolean;
begin
// Really UniCodeCompareStr (Annoying VCL Name for backwards compatablity)
Result := AnsiCompareStr(ASource.ToString, ADestination.ToString) = 0;
end;
class function TRttiUtils.ExistsProperty(AObject: TObject; const APropertyName: string;
out AProperty: TRttiProperty): Boolean;
begin
AProperty := GlContext.GetType(AObject.ClassInfo).GetProperty(APropertyName);
Result := Assigned(AProperty);
end;
class function TRttiUtils.FindByProperty<T>(AList: TObjectList<T>; APropertyName: string; APropertyValue: TValue): T;
var
elem: T;
V: TValue;
Found: Boolean;
begin
Found := False;
for elem in AList do
begin
V := GetProperty(elem, APropertyName);
case V.Kind of
tkInteger:
Found := V.AsInteger = APropertyValue.AsInteger;
tkFloat:
Found := abs(V.AsExtended - APropertyValue.AsExtended) < 0.001;
tkString, tkLString, tkWString, tkUString:
Found := V.AsString = APropertyValue.AsString;
tkInt64:
Found := V.AsInt64 = APropertyValue.AsInt64;
else
raise Exception.Create('Property type not supported');
end;
if Found then
Exit(elem);
end;
Result := nil;
end;
class function TRttiUtils.FindType(AQualifiedName: string): TRttiType;
begin
Result := GlContext.FindType(AQualifiedName);
end;
class procedure TRttiUtils.ForEachProperty(AClazz: TClass; AProc: TProc<TRttiProperty>);
var
_rtti: TRttiType;
P: TRttiProperty;
begin
_rtti := GlContext.GetType(AClazz);
if Assigned(_rtti) then
begin
for P in _rtti.GetProperties do
AProc(P);
end;
end;
class procedure TRttiUtils.CopyObject(ASourceObject, ATargetObject: TObject);
var
_ARttiType: TRttiType;
Field: TRttiField;
master, cloned: TObject;
Src: TObject;
sourceStream: TStream;
SavedPosition: Int64;
targetStream: TStream;
targetCollection: IWrappedList;
sourceCollection: IWrappedList;
I: Integer;
sourceObject: TObject;
targetObject: TObject;
Tar: TObject;
begin
if not Assigned(ATargetObject) then
Exit;
_ARttiType := GlContext.GetType(ASourceObject.ClassType);
cloned := ATargetObject;
master := ASourceObject;
for Field in _ARttiType.GetFields do
begin
if not Field.FieldType.IsInstance then
Field.SetValue(cloned, Field.GetValue(master))
else
begin
Src := Field.GetValue(ASourceObject).AsObject;
if Src is TStream then
begin
sourceStream := TStream(Src);
SavedPosition := sourceStream.Position;
sourceStream.Position := 0;
if Field.GetValue(cloned).IsEmpty then
begin
targetStream := TMemoryStream.Create;
Field.SetValue(cloned, targetStream);
end
else
targetStream := Field.GetValue(cloned).AsObject as TStream;
targetStream.Position := 0;
targetStream.CopyFrom(sourceStream, sourceStream.Size);
targetStream.Position := SavedPosition;
sourceStream.Position := SavedPosition;
end
else if TDuckTypedList.CanBeWrappedAsList(Src) then
begin
sourceCollection := WrapAsList(Src);
Tar := Field.GetValue(cloned).AsObject;
if Assigned(Tar) then
begin
targetCollection := WrapAsList(Tar);
targetCollection.Clear;
for I := 0 to sourceCollection.Count - 1 do
targetCollection.Add(TRttiUtils.Clone(sourceCollection.GetItem(I)));
end;
end
else
begin
sourceObject := Src;
if Field.GetValue(cloned).IsEmpty then
begin
targetObject := TRttiUtils.Clone(sourceObject);
Field.SetValue(cloned, targetObject);
end
else
begin
targetObject := Field.GetValue(cloned).AsObject;
TRttiUtils.CopyObject(sourceObject, targetObject);
end;
end;
end;
end;
end;
{$IF CompilerVersion >= 24.0}
class procedure TRttiUtils.CopyObjectAS<T>(ASourceObject, ATargetObject: TObject);
var
_ARttiType: TRttiType;
_ARttiTypeTarget: TRttiType;
Field, FieldDest: TRttiField;
master, cloned: TObject;
Src: TObject;
sourceStream: TStream;
SavedPosition: Int64;
targetStream: TStream;
targetCollection: IWrappedList;
sourceCollection: IWrappedList;
I: Integer;
sourceObject: TObject;
targetObject: TObject;
Tar: TObject;
begin
if not Assigned(ATargetObject) then
Exit;
_ARttiType := GlContext.GetType(ASourceObject.ClassType);
_ARttiTypeTarget := GlContext.GetType(ATargetObject.ClassType);
cloned := ATargetObject;
master := ASourceObject;
for Field in _ARttiType.GetFields do
begin
FieldDest := _ARttiTypeTarget.GetField(Field.Name);
if not Assigned(FieldDest) then
continue;
if not Field.FieldType.IsInstance then
begin
FieldDest.SetValue(cloned, Field.GetValue(master));
end
else
begin
Src := Field.GetValue(ASourceObject).AsObject;
if not Assigned(Src) then
begin
FieldDest.SetValue(cloned, Src);
end
else if Src is TStream then
begin
sourceStream := TStream(Src);
SavedPosition := sourceStream.Position;
sourceStream.Position := 0;
if FieldDest.GetValue(cloned).IsEmpty then
begin
targetStream := TMemoryStream.Create;
FieldDest.SetValue(cloned, targetStream);
end
else
targetStream := FieldDest.GetValue(cloned).AsObject as TStream;
targetStream.Position := 0;
targetStream.CopyFrom(sourceStream, sourceStream.Size);
targetStream.Position := SavedPosition;
sourceStream.Position := SavedPosition;
end
else if TDuckTypedList.CanBeWrappedAsList(Src) then
begin
sourceCollection := WrapAsList(Src);
Tar := FieldDest.GetValue(cloned).AsObject;
if Assigned(Tar) then
begin
targetCollection := WrapAsList(Tar);
targetCollection.Clear;
for I := 0 to sourceCollection.Count - 1 do
targetCollection.Add(TRttiUtils.Clone(sourceCollection.GetItem(I)));
end;
end
else
begin
sourceObject := Src;
if FieldDest.GetValue(cloned).IsEmpty then
begin
targetObject := TRttiUtils.Clone(sourceObject);
FieldDest.SetValue(cloned, targetObject);
end
else
begin
targetObject := FieldDest.GetValue(cloned).AsObject;
TRttiUtils.CopyObject(sourceObject, targetObject);
end;
end;
end;
end;
end;
{$ENDIF}
class constructor TRttiUtils.Create;
begin
GlContext := TRttiContext.Create;
end;
class function TRttiUtils.CreateObject(AQualifiedClassName: string; const AParams: TArray<TValue> = nil): TObject;
var
rttitype: TRttiType;
begin
rttitype := GlContext.FindType(AQualifiedClassName);
if Assigned(rttitype) then
Result := CreateObject(rttitype, AParams)
else
raise Exception.Create('Cannot find RTTI for ' + AQualifiedClassName +
'. Hint: Is the specified classtype linked in the module?');
end;
class function TRttiUtils.CreateObject(ARttiType: TRttiType; const AParams: TArray<TValue> = nil): TObject;
var
Method: TRttiMethod;
metaClass: TClass;
lParamsCount: Integer;
begin
if AParams = nil then
begin
lParamsCount := 0;
end
else
begin
lParamsCount := Length(AParams);
end;
{ First solution, clear and slow }
metaClass := nil;
Method := nil;
for Method in ARttiType.GetMethods do
begin
if Method.HasExtendedInfo and Method.IsConstructor then
begin
if Length(Method.GetParameters) = lParamsCount then
begin
metaClass := ARttiType.AsInstance.MetaclassType;
Break;
end;
end;
end;
if Assigned(metaClass) then
begin
if AParams = nil then
begin
Result := Method.Invoke(metaClass, []).AsObject;
end
else
begin
Result := Method.Invoke(metaClass, AParams).AsObject;
end;
end
else
begin
raise Exception.Create('Cannot find a parameterless constructor for ' + ARttiType.ToString);
end;
{ Second solution, dirty and fast }
// Result := TObject(ARttiType.GetMethod('Create')
// .Invoke(ARttiType.AsInstance.MetaclassType, []).AsObject);
end;
class function TRttiUtils.BuildClass(AQualifiedName: string; AParams: array of TValue): TObject;
var
T: TRttiType;
V: TValue;
begin
T := FindType(AQualifiedName);
V := T.GetMethod('Create').Invoke(T.AsInstance.MetaclassType, AParams);
Result := V.AsObject;
end;
class function TRttiUtils.Clone(AObject: TObject): TObject;
var
_ARttiType: TRttiType;
Field: TRttiField;
master, cloned: TObject;
Src: TObject;
sourceStream: TStream;
SavedPosition: Int64;
targetStream: TStream;
targetCollection: TObjectList<TObject>;
sourceCollection: TObjectList<TObject>;
I: Integer;
sourceObject: TObject;
targetObject: TObject;
begin
Result := nil;
if not Assigned(AObject) then
Exit;
_ARttiType := GlContext.GetType(AObject.ClassType);
cloned := CreateObject(_ARttiType);
master := AObject;
for Field in _ARttiType.GetFields do
begin
if not Field.FieldType.IsInstance then
Field.SetValue(cloned, Field.GetValue(master))
else
begin
Src := Field.GetValue(AObject).AsObject;
if Src is TStream then
begin
sourceStream := TStream(Src);
SavedPosition := sourceStream.Position;
sourceStream.Position := 0;
if Field.GetValue(cloned).IsEmpty then
begin
targetStream := TMemoryStream.Create;
Field.SetValue(cloned, targetStream);
end
else
targetStream := Field.GetValue(cloned).AsObject as TStream;
targetStream.Position := 0;
targetStream.CopyFrom(sourceStream, sourceStream.Size);
targetStream.Position := SavedPosition;
sourceStream.Position := SavedPosition;
end
else if Src is TObjectList<TObject> then
begin
sourceCollection := TObjectList<TObject>(Src);
if Field.GetValue(cloned).IsEmpty then
begin
targetCollection := TObjectList<TObject>.Create;
Field.SetValue(cloned, targetCollection);
end
else
targetCollection := Field.GetValue(cloned).AsObject as TObjectList<TObject>;
for I := 0 to sourceCollection.Count - 1 do
begin
targetCollection.Add(TRttiUtils.Clone(sourceCollection[I]));
end;
end
else
begin
sourceObject := Src;
if Field.GetValue(cloned).IsEmpty then
begin
targetObject := TRttiUtils.Clone(sourceObject);
Field.SetValue(cloned, targetObject);
end
else
begin
targetObject := Field.GetValue(cloned).AsObject;
TRttiUtils.CopyObject(sourceObject, targetObject);
end;
Field.SetValue(cloned, targetObject);
end;
end;
end;
Result := cloned;
end;
class function TRttiUtils.HasAttribute<T>(AObject: TObject; out AAttribute: T): Boolean;
begin
Result := HasAttribute<T>(GlContext.GetType(AObject.ClassType), AAttribute)
end;
{$IF not defined(BERLINORBETTER)}
{ TValueHelper }
function TValueHelper.IsObjectInstance: Boolean;
begin
Result := (Self.TypeInfo <> nil) and (Self.TypeInfo^.Kind = tkClass);
end;
{$ENDIF}
end.