Send JSON over TCP connection

[mandoza]

Zitat von TiGü:

Please be aware, in this way you serialize the internal structure of the TDepartmentList.

Code:

'{"ownsObjects":true,"listHelper":[2],"items":[{"deptName":"Finance","deptID":10},{"deptName":"HUMAN RESOURCE","deptID":11}]}'

Is there any issue with that ( network latency ... etc ) ?
Please any other better way .

[Sherlock]

Hi mandoza, I would like to remind you, that we have a fine english speaking sibling to this forum found here: en.delphipraxis.net.

Sherlock

[TiGü]

Zitat von mandoza:

Is there any issue with that ( network latency ... etc ) ?
Please any other better way .

It's unnessacry overhead and can't properly parsed in other dev environments.
Imagine if someone with Javascript, C++ or something else want to parse your JSON with ownObjects and listHelper.

You can workaround this with a simple data transfer object (DTO).

Code:

'{"items":[{"deptName":"Finance","deptID":10},{"deptName":"HUMAN RESOURCE","deptID":11}]}'

Delphi-Quellcode:

program Project1;

{$APPTYPE CONSOLE}
{$R *.res}

uses
    Department in 'Department.pas',
    System.SysUtils,
    REST.Json;

Procedure SerializeAndSend;
var
    DepartmentList, DepartmentList2: TDepartmentList;
    Department: TDepartment;
    Json: string;
    DepartmentsInfo: TDepartmentsInfo;
    DepartmentStore: TDepartmentStore;
begin
    DepartmentList := TDepartmentList.Create;
    try
        Department := TDepartment.Create;
        Department.DeptName := 'Finance';
        Department.DeptID := 10;
        DepartmentList.Add(Department);

        Department := TDepartment.Create;
        Department.DeptName := 'HUMAN RESOURCE';
        Department.DeptID := 11;
        DepartmentList.Add(Department);

        DepartmentStore := TDepartmentStore.Create(DepartmentList.ToArray);
        try
            Json := TJson.ObjectToJsonString(DepartmentStore);
        finally
            DepartmentStore.Free;
        end;

    finally
        DepartmentList.Free();
    end;

    DepartmentsInfo.Packet_ID := 1;
    DepartmentsInfo.DeptInfo := Json.ToCharArray;
    SocketSendDeptInfo(@DepartmentsInfo, DepartmentsInfo.BuffSize);

    // Deserialization
    DepartmentStore := TJson.JsonToObject<TDepartmentStore>(Json);
    DepartmentList2 := TDepartmentList.Create();
    try
        DepartmentList2.AddRange(DepartmentStore.Items);
    finally
        DepartmentList2.Free;
    end;
end;

begin
    SerializeAndSend;
    Readln;

end.

Delphi-Quellcode:

unit Department;

interface

uses
    System.SysUtils,
    System.Generics.Collections,
    REST.Json,
    System.Rtti;

type
    TDepartmentsInfo = Packed Record
        Packet_ID: Integer;
        DeptInfo: TArray<Char>; // This will hold the JSON converted class
        function BuffSize: Integer;
    end;

    PDepartmentsInfo = ^TDepartmentsInfo;

type
    TDepartment = class
    strict private
        FDeptName: string;
        FDeptID: Integer;
    public
        property DeptName: string read FDeptName write FDeptName;
        property DeptID: Integer read FDeptID write FDeptID;
    end;

    TDepartmentList = class(TObjectList<TDepartment>);

    TDepartmentStore = class
    private
        FItems: TArray<TDepartment>;
    public
        constructor Create(const AItems: TArray<TDepartment>);
        property Items: TArray<TDepartment> read FItems;
    end;

procedure SocketSendDeptInfo(const DepartmentsInfo: PDepartmentsInfo;
  BufferSize: Integer);

implementation

function TDepartmentsInfo.BuffSize: Integer;
begin
    Result := SizeOf(Packet_ID) + (SizeOf(Char) * Length(DeptInfo));
end;

procedure SocketSendDeptInfo(const DepartmentsInfo: PDepartmentsInfo;
  BufferSize: Integer);
begin

end;

constructor TDepartmentStore.Create(const AItems: TArray<TDepartment>);
begin
    FItems := AItems;
end;

end.

[Schokohase]

Talking about overhead ... why not remove all overhead?

Code:

[
  {
    "deptName": "Finance",
    "deptID": 10
  },
  {
    "deptName": "HUMAN RESOURCE",
    "deptID": 11
  }
]

contains the same information as

Code:

{
  "items": [
    {
      "deptName": "Finance",
      "deptID": 10
    },
    {
      "deptName": "HUMAN RESOURCE",
      "deptID": 11
    }
  ]
}

but with less chars (overhead).

[jobo]

Zitat von Neutral General:

Courtesy and respect? Really?

In my point of view, posting questions and asking for help should include these points.
Asking sames question in different communities without letting each other know, forces people to waste their power and time. That's disrespectful in my point of view.

Although he apologized and seems to understand the problem, he didn't link to this post on SO.

And pretending that's all new .. doesn't make it any better.