IDataStore.ReselectRow(int row) Method

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

0.5.0-alpha

1.0.1 (current)

Accesses the database to retrieve values for all columns that can be updated and refreshes all timestamp columns in a row in the DataStore.

Namespace: PowerBuilder.Data

Assembly: PowerBuilder.Data.dll

Syntax

  public int ReselectRow(int row);

Parameters

row System.Int32

A zero-based number identifying the row to reselect.

Returns

System.Int32

Returns 1 if it succeeds and -1 if the row cannot be reselected (for example, the DataStore cannot be updated or the row was deleted by another user).

Remarks

ReselectRow is supported for SQL Select DataStore. Use ReselectRow to discard values the user has changed and replace them with values from the database after an update fails (due to a concurrent access error, for example).

Examples

The following code example modifies the values for row 1 and then calls the ReselectRow method to retrieve the original values for row 1 from database again.

using PowerBuilder.Data;
using System;

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

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

        public void Example()
        {
            // Instantiates a DataStore object with datawindow: d_department.
            var datastore = new DataStore("d_department", _context);

            datastore.Retrieve();

            Console.WriteLine("Department ID: {0}; Department Name: {1}",
                               datastore.GetItem<int>(0, "departmentid"),
                               datastore.GetItem<string>(0, "name"));

            // Modified the values for row 1.
            datastore.SetItem(0, "departmentid", 10);
            datastore.SetItem(0, "name", "Department Name");

            Console.WriteLine("Department ID: {0}; Department Name: {1}",
                               datastore.GetItem<int>(0, "departmentid"),
                               datastore.GetItem<string>(0, "name"));

            // Calls ReselectRow to retrieve values for row 1 from database again.
            // It will send SQL commands to database.
            datastore.ReselectRow(0);

            Console.WriteLine("Department ID: {0}; Department Name: {1}",
                               datastore.GetItem<int>(0, "departmentid"),
                               datastore.GetItem<string>(0, "name"));

            /*This code produces the following output:
             
            Department ID: 1; Department Name: Engineering
            Department ID: 10; Department Name: Department Name
            Department ID: 1; Department Name: Engineering
            */
        }
    }
}

Example Refer To

Model Class: D_Department
DataWindow File: d_department

Applies to

.NET Standard

2.x