IObjectDataSourceValidationService.Validate(IEnumerable<ObjectDataSource>) Method

Validates the ObjectDataSource data objects before data retrieval.

Namespace: DevExpress.XtraSpreadsheet.Services

Assembly: DevExpress.Spreadsheet.v19.1.Core.dll

Declaration

C#

void Validate(
    IEnumerable<ObjectDataSource> dataSources
)

VB.NET

Sub Validate(
    dataSources As IEnumerable(Of ObjectDataSource)
)

Parameters

Name	Type	Description
dataSources	IEnumerable<ObjectDataSource>	An IEnumerable<T><ObjectDataSource,> collection to validate.

Remarks

To prevent a data object in a collection from executing its data retrieval method, set its ObjectDataSource.DataSource and ObjectDataSource.DataMember properties to null.

Example

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-validate-the-objectdatasource-contained-in-the-spreadsheet-mailmerge-template-t514794

Form1.vb

Imports DevExpress.DataAccess.ObjectBinding
Imports DevExpress.XtraSpreadsheet.Services
            If barCheckCustomValidationService.Checked Then
                spreadsheetControl1.ReplaceService(Of IObjectDataSourceValidationService)(New MyObjectDataSourceValidationService())
            Else
                spreadsheetControl1.ReplaceService(Of IObjectDataSourceValidationService)(New ObjectDataSourceValidationService(spreadsheetControl1))
            End If
    Public Class MyObjectDataSourceValidationService
        Implements IObjectDataSourceValidationService

        Public Sub Validate(ByVal dataSources As IEnumerable(Of ObjectDataSource)) Implements IObjectDataSourceValidationService.Validate
            ' Do nothing to allow loading.
            ' Clear the DataSource and DataMember properties to prohibit loading.
            For Each ds As ObjectDataSource In dataSources
                ds.DataSource = Nothing
                ds.DataMember = Nothing
            Next ds
        End Sub
    End Class

Form1.cs

using DevExpress.DataAccess.ObjectBinding;
using DevExpress.XtraSpreadsheet.Services;
            if (barCheckCustomValidationService.Checked) {
                spreadsheetControl1.ReplaceService<IObjectDataSourceValidationService>(new MyObjectDataSourceValidationService());
            }
            else {
                spreadsheetControl1.ReplaceService<IObjectDataSourceValidationService>(new ObjectDataSourceValidationService(spreadsheetControl1));
            }
    public class MyObjectDataSourceValidationService : IObjectDataSourceValidationService {
        public void Validate(IEnumerable<ObjectDataSource> dataSources) {
            // Do nothing to allow loading.
            // Clear the DataSource and DataMember properties to prohibit loading.
            foreach (ObjectDataSource ds in dataSources) {
                ds.DataSource = null;
                ds.DataMember = null;
            };
        }
    }