Using DataSetAdapter.Get

[rasaliad]

Hi Mr. Sanchez

I begin to use RESTRequest4Delphi and I want to now which property to setup to use GET with DataSetAdapter with the following JSon from a third party Application. I only need the "r" field to fill the dataset.

Thanks,

{
"a": 200,
"r": [
{
"category_id": 2,
"id": 1,
"product_price": 99.9,
"product_code": "T001",
"product_name": "Teddy Bear"
},
{
"category_id": 2,
"id": 3,
"product_price": 100,
"product_code": "T002",
"product_name": "Optimus Prime"
},
{
"category_id": 2,
"id": 4,
"product_price": 258,
"product_code": "1234",
"product_name": "Bob light year"
},
{
"category_id": 2,
"id": 6,
"product_price": 325,
"product_code": "monop",
"product_name": "monopolio"
}
],
"s": "ok",
"e": "null",
"m": "Success"
}

[viniciussanchez]

You will have to get the JSON manually. And load into your dataset. JSON automatically loads the first level just... a, r, s, e, m. You can also create a Master Detail DataSet. Then it would work... but the simplest way would be to get the JSON manually and load only what you need.

uses RESTRequest4Delphi, DataSet.Serialize;

var
  LResponse: IResponse;
begin
  LResponse := TRequest.New.BaseURL('').Get;
  if LResponse.StatusCode = 200 then
    DataSet.LoadFromJSON(LResponse.JSONValue.GetValue<TJSONArray>('r'));

[rasaliad]

Thank Mr. Sanchez

It works!!!,

I have to add .ToJSON , if not, the dataset get filled but and accesviolation occurs

I change from:

// Fill the dataset but get a accesviolation error

mt1.LoadFromJSON(LResponse.JSONValue.GetValue<TJSONArray>('r'));

to:

// Fill the dataset and no error occurs

mt1.LoadFromJSON(LResponse.JSONValue.GetValue<TJSONArray>('r').ToJSON);

Thanks again. And yours tools are very powerful, i have to learn more about it.

Rafael

[viniciussanchez]

Another alternative would be to pass the second parameter as false, like this:

mt1.LoadFromJSON(LResponse.JSONValue.GetValue<TJSONArray>('r'), False);

[mariolandossa]

@viniciussanchez como ficaria isso no Lazarus já que a propriedade GetValue não existe