freepascal TJsonDataset
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 | unit Unit1; {$mode objfpc}{$H+} interface uses Classes, SysUtils, Forms, Controls, Graphics, Dialogs, DBCtrls, DBGrids, DB, fpjson, fpjsondataset; type TForm1 = class (TForm) DataSource1: TDataSource; DBGrid1: TDBGrid; procedure FormCreate(Sender: TObject); private JSONDataSet: TJSONDataSet; end; var Form1: TForm1; const // this is the sample JSON data used in the demo JSON_STRING = '[' + '{"Author ID":"409-56-7008","Last Name":"Bennet","First Name":"Abraham","Active": False},' + '{"Author ID":"213-46-8915","Last Name":"Green","First Name":"Marjorie","Active": True}' + ']' ; implementation {$R *.lfm} procedure TForm1.FormCreate(Sender: TObject); var data: TJSONArray; begin // parse the JSON string data := GetJSON(JSON_STRING) as TJSONArray; // create a new TJSONDataSet JSONDataSet := TJSONDataSet.Create(Self); // you'll need to create the FieldDefs manually // ftString requires a length specified JSONDataSet.FieldDefs.Add( 'Author ID' , ftString, 11, True); JSONDataSet.FieldDefs.Add( 'Last Name' , ftString, 40); JSONDataSet.FieldDefs.Add( 'First Name' , ftString, 20); JSONDataSet.FieldDefs.Add( 'Active' , ftBoolean); // set OwnsData to True, and the JSON data will be destroyed when the dataset is destroyed JSONDataSet.OwnsData := True; // the JSON data is an array of objects JSONDataSet.RowType := rtJSONObject; // assign the JSON data to the dataset JSONDataSet.Rows := data; // activate the dataset JSONDataSet.Active := True; // assign the dataset to the datasource DataSource1.DataSet := JSONDataSet; end; end. |
1 2 3 4 5 6 7 8 9 10 11 | procedure TForm1.Button1Click(Sender: TObject); begin JSONDataSet1.FieldDefs.Add( 'id' , ftstring, 9); JSONDataSet1.FieldDefs.Add( 'name' , ftstring, 9); JSONDataSet1.Open; JSONDataSet1.Append; JSONDataSet1[ 'id' ] := '1' ; JSONDataSet1[ 'name' ]:= '中' ; JSONDataSet1.Post; memo1.Text:= JSONDataSet1.Rows.Clone.AsJSON; //[{ "id" : "1", "name" : "中" }] end; |
本文来自博客园,作者:{咏南中间件},转载请注明原文链接:https://www.cnblogs.com/hnxxcxg/p/18148565
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