标签:des http io os ar for 数据 sp art
一)服务器端代码演示
1)常量定义:
const
sDepartment = ‘Department‘;
sEmployees = ‘Employees‘;
2)查询数据:
function TServerMethods1.GetDepartmentEmployees(const AID: string): TFDJSONDataSets;
begin
// Clear active so that query will reexecute.
FDQueryDepartmentEmployees.Active := False;
FDQueryDepartment.Active := False;
FDQueryDepartment.Params[0].Value := AID;
FDQueryDepartmentEmployees.Params[0].Value := AID;
// Create dataset list
Result := TFDJSONDataSets.Create;
// Add departments dataset
TFDJSONDataSetsWriter.ListAdd(Result, sDepartment, FDQueryDepartment);
// Add employees dataset
TFDJSONDataSetsWriter.ListAdd(Result, sEmployees, FDQueryDepartmentEmployees);
end;
TFDJSONDataSets,FIREDAC的数据集列表对象,可返回多个数据集。
3)提交数据:
procedure TServerMethods1.ApplyChangesDepartmentEmployees( const ADeltaList: TFDJSONDeltas); var LApply: IFDJSONDeltasApplyUpdates; begin // Create the apply object LApply := TFDJSONDeltasApplyUpdates.Create(ADeltaList); // Apply the department delta LApply.ApplyUpdates(sDepartment, FDQueryDepartment.Command); if LApply.Errors.Count = 0 then // If no errors, apply the employee delta LApply.ApplyUpdates(sEmployees, FDQueryDepartmentEmployees.Command); if LApply.Errors.Count > 0 then // Raise an exception if any errors. raise Exception.Create(LApply.Errors.Strings.Text); end;
二)客户端演示代码
1)查询数据:
procedure TForm2.GetDepartmentEmployees(const ADEPTNO: string);
var
LDataSetList: TFDJSONDataSets;
LDataSet: TFDDataSet;
begin
LDataSetList := ClientModule1.ServerMethods1Client.GetDepartmentEmployees(ADEPTNO);
// Get department dataset
LDataSet := TFDJSONDataSetsReader.GetListValueByName(LDataSetList,sDepartment);
// Update UI
FDMemTableDepartment.Active := False;
FDMemTableDepartment.AppendData(LDataSet);
// Get employees dataset
LDataSet := TFDJSONDataSetsReader.GetListValueByName(LDataSetList, sEmployees);
// Update UI
FDMemTableEmployee.Active := False;
FDMemTableEmployee.AppendData(LDataSet);
end;
2)提交数据:
function TForm2.GetDeltas: TFDJSONDeltas; begin // Post if editing if FDMemTableDepartment.State in dsEditModes then begin FDMemTableDepartment.Post; end; if FDMemTableEmployee.State in dsEditModes then begin FDMemTableEmployee.Post; end; // Create a delta list Result := TFDJSONDeltas.Create; // Add deltas TFDJSONDeltasWriter.ListAdd(Result, sEmployees, FDMemTableEmployee); TFDJSONDeltasWriter.ListAdd(Result, sDepartment, FDMemTableDepartment); end;
procedure TForm2.ApplyUpdates; var LDeltaList: TFDJSONDeltas; begin LDeltaList := GetDeltas; // Call server method. Pass the delta list. ClientModule1.ServerMethods1Client.ApplyChangesDepartmentEmployees(LDeltaList); end;
注意:
服务端和客户端都要放置2个控件:
TFDStanStorageJSONLink
TFDStanStorageBinLink
FIREDAC的TFDJSONDataSets和TFDJSONDeltas
标签:des http io os ar for 数据 sp art
原文地址:http://www.cnblogs.com/hnxxcxg/p/4008789.html