Firedac's Tfdjsondatasets and Tfdjsondeltas

A) server-side code demo
1) Constant definition:
Const  ' Department ';  ' Employees ';   

2) query data:

function TServerMethods1.Getdepartmentemployees(Const AID:String): Tfdjsondatasets;BeginClear active So, query would 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//ADD employees DataSet Tfdjsondatasetswriter. Listadd ; End              

The TFDJSONDATASETS,FIREDAC DataSet list object, which returns multiple datasets.

3) Submit data:

Procedure TServerMethods1.Applychangesdepartmentemployees(Const ADELTALIST: Tfdjsondeltas);var lapply: ifdjsondeltasapplyupdates;BeginCreate the Apply Object lapply:= Tfdjsondeltasapplyupdates.Create(adeltalist);Apply the Department Delta Lapply.Applyupdates(sdepartment, fdquerydepartment.Command);If lapply.Errors.Count=0ThenIf no errors, apply the employee Delta Lapply. applyupdates(semployees, Fdquerydepartmentemployees.  Command); if lapply.  Errors.  Count > 0 then //Raise A exception if any errors. raise Exception.  Create(lapply.  Errors.  Strings.  Text);  End;

II) client Demo code
1) query data:

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) Submit data:

function TForm2.Getdeltas: Tfdjsondeltas;BeginPost if editingIf fdmemtabledepartment.StateIn DseditmodesThenBegin Fdmemtabledepartment.Post;End;If Fdmemtableemployee.StateIn DseditmodesThenbegin 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;:= Getdeltas//Call server method. Pass the Delta list. ClientModule1.  Servermethods1client.  Applychangesdepartmentemployees(ldeltalist); end;                 

Attention:
There are 2 controls to be placed on both the server and the client:
Tfdstanstoragejsonlink
Tfdstanstoragebinlink

       

              

Firedac Tfdjsondatasets and Tfdjsondeltas