IDataStore.ImportJson(string json, DwBuffer dwbuffer, int startRow, int endRow, int startColumn) Method

.NET Standard 2.x | Current Version (1.0.1)

0.5.0-alpha

1.0.1 (current)

Inserts data from a JSON string into the specified buffer of DataStore. You can specify the starting and ending positions in the JSON array, and you can specify the number of the first key value in the JSON object to be imported. Data that are out of this range will not be imported into the DataStore.

Namespace: PowerBuilder.Data

Assembly: PowerBuilder.Data.dll

Syntax

  public int ImportJson(string json, DwBuffer dwbuffer, int startRow, int endRow, int startColumn);

Parameters

json System.String

A string specifying the JSON data.

The JSON string must comply with the plain-format JSON or DataWindow JSON.

dwbuffer PowerBuilder.Data.DwBuffer

The specified buffer of the DataStore.

A value of the DwBuffer enumerated datatype identifying the DataWindow buffer into which you want to import the data.

For plain-format JSON: Imports the JSON data to the specified buffer.

For DataWindow JSON: Imports data from the specified buffer from the JSON string to the corresponding buffer.

startRow System.Int32

The zero-based number of the first detail object in the JSON array that you want to import. If it is negative, 0 is used.

endRow System.Int32

The zero-based number of the last detail object in the JSON array that you want to import. If it is negative, it indicates the rest of rows.

startColumn System.Int32

The zero-based number of the first key value in the JSON object that you want to import. If it is negative, 0 is used.

Returns

System.Int32

Returns the number of rows that were imported if it succeeds.

Examples

The following code example demonstrates how to import the department data from between the starting row and the ending row and from the starting column in a JSON string to the specified buffer.

using PowerBuilder.Data;
using System;
using System.IO;

namespace Appeon.ApiDoc.IDataStoreExamples
{
    public class ImportJsonExample
    {
        private SchoolContext _context;

        public ImportJsonExample(SchoolContext dataContext)
        {
            // Sets the data context
            _context = dataContext;
        }

        public void Example5()
        {
            // Instantiates the datastore with datawindow: d_department2
            // d_department2 has no departmentID column
            var datastore = new DataStore("d_department2", _context);

            // Gets the JSON file. ImportJson8.json contains 4 records.
            string path = Path.Combine(AppContext.BaseDirectory,
                                @"Jsons\IDatastore\ImportJson8.json");
            string json = File.ReadAllText(path);

            // Imports data from JSON to the primary buffer.
            // Imports data from row 1 through the end.
            // Imports data starting from column 2. Column 1 will not be imported.
            datastore.ImportJson(json, DwBuffer.Primary, 0, 3, 1);

            Console.WriteLine("Rowcount: {0}", datastore.RowCount);

            for (int row = 0, rowcount = datastore.RowCount; row < rowcount; row++)
            {
                Console.WriteLine("Name: {0}; Budget: {1}",
                                  datastore.GetItem<string>(row, "name"),
                                  datastore.GetItem<decimal>(row, "budget"));
            }

            datastore.Reset();

            // Imports data from row 2 and 3 of the JSON string to the primary buffer.
            // Imports data starting from column 2 of the JSON string. 
            // Column 1 will not be imported.
            datastore.ImportJson(json, DwBuffer.Primary, 1, 2, 1);

            Console.WriteLine("Rowcount: {0}", datastore.RowCount);

            for (int row = 0, rowcount = datastore.RowCount; row < rowcount; row++)
            {
                Console.WriteLine("Name: {0}; Budget: {1}",
                                  datastore.GetItem<string>(row, "name"),
                                  datastore.GetItem<decimal>(row, "budget"));
            }

            /*This code produces the following output:

            Rowcount: 4
            Name: Engineering; Budget: 350000
            Name: English; Budget: 120000
            Name: Economics; Budget: 200000
            Name: Mathematics; Budget: 250000
            Rowcount: 2
            Name: English; Budget: 120000
            Name: Economics; Budget: 200000
           */
        }
    }
}

Example Refer To

JSON File: ImportJson8

Applies to

.NET Standard

2.x