IDwDataImporter.ImportByKey(string text, DwBuffer dwbuffer, int startRow, int endRow) Method

.NET Standard 2.x

Imports data into the specified buffer of DataStore with the specified DataFormat based on the key name, and specifies the start and end positions of the rows.

Namespace: DWNet.Data

Assembly: DWNet.Data.dll

Syntax

int ImportByKey(string text, DwBuffer dwbuffer, int startRow, int endRow);

text System.String

Data string in the specified format.

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

dwbuffer DWNet.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 index number of the first row in the buffer that you want to export.

endRow System.Int32

The zero-based index number of the last row in the buffer that you want to export.

If it is negative, it indicates the rest of rows.

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 of a JSON string to the specified DataStore buffer.

using DWNet.Data;
using SnapObjects.Data;
using System;
using System.IO;

namespace Appeon.ApiDoc.IDwDataImporterExamples
{
    public class ImportByKeyExample
    {
        private readonly SchoolContext _context;

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

        public void Example4()
        {
            // Instantiates the datastore with datawindow: d_department2
            var datastore = new DataStore("d_department2", _context);

            // Get DataStore importer in JSON format.
            var importer = datastore.GetDataImporter(DataFormat.Json);

            // Gets the JSON file,ExportPlainJson1.json contains 4 records.
            string path = Path.Combine(AppContext.BaseDirectory,
                                @"Jsons\IDwDataExporter\ExportPlainJson1.json");
            string json = File.ReadAllText(path);

            // Imports data from JSON to the DataStore primary buffer, from row 1 
            // through the end.
            // The departmentid column exists in ImportJson8.json, but not in 
            // DataStore d_department2.
            // But ImportJsonByKey imports data by the column name, so departmentid 
            // will be ignored.
            int row = importer.ImportByKey(json, DwBuffer.Primary, 0, 3);

            Console.WriteLine("Import Row: {0}; Rowcount: {1}", row, datastore.RowCount);

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

            datastore.Reset();

            // Imports data from row 2 and 3.
            // The departmentid column exists in ImportJson8.json, but not in DataStore 
            // d_department2.
            // But ImportJsonByKey imports data by the column name, so departmentid 
            // will be ignored.
            row = importer.ImportByKey(json, DwBuffer.Primary, 1, 2);

            Console.WriteLine("Import Row: {0}; Rowcount: {1}", row, datastore.RowCount);

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

            /*This code produces the following output:

            Import Row: 4; Rowcount: 4
            Name: Engineering; Budget: 350000
            Name: English; Budget: 120000
            Name: Economics; Budget: 200000
            Name: Mathematics; Budget: 250000

            Import Row: 2; Rowcount: 2
            Name: English; Budget: 120000
            Name: Economics; Budget: 200000
           */
        }
    }
}

Example Refer To

Model Class: D_Department2
JSON File: ExportPlainJson1
DataWindow File: d_department2