corelibraries-devexpress-dot-dataaccess-dot-sql-ec724951.md
Allows you to intercept commands sent to a relational database.
Namespace : DevExpress.DataAccess.Sql
Assembly : DevExpress.DataAccess.v25.2.dll
NuGet Package : DevExpress.DataAccess
public interface IDBCommandInterceptor
Public Interface IDBCommandInterceptor
The following members return IDBCommandInterceptor objects:
| Library | Related API Members |
|---|---|
| WinForms Controls | EditQueryContext.CommandInterceptor |
| Dashboard | DashboardDesigner.CustomDBCommandInterceptor |
| DashboardViewer.CustomDBCommandInterceptor | |
| IDashboardControl.CustomDBCommandInterceptor |
Dashboard and report controls execute a variety of SQL statements against the database. Implement IDBCommandInterceptor to intercept these data source commands. You can suppress a command or modify the execution algorithm.
You can register interceptors in service providers of dashboard or report controls. The registration method depends on the control type and platform:
IDBCommandInterceptor object to the control’s CustomDBCommandInterceptor property. For example, use the DashboardDesigner.CustomDBCommandInterceptor property.IDBCommandInterceptor object as an extension in IServiceCollection.The following example shows how to override the default isolation level (READ COMMITTED) in a specific query. The change allows users to retrieve information without being locked by another process that modifies the same data. This way, the query consumes less memory.
IDBCommandInterceptor interface (NolockInterceptor.cs in this example). Call the IDBCommandInterceptor.CommandCreated(String, IDbCommand) method and specify CommandText to execute.using DevExpress.DataAccess.Sql;
using System.Data;
namespace XtraReportApp {
internal class NolockInterceptor : IDBCommandInterceptor {
public void CommandCreated(string queryName, IDbCommand command) {
command.CommandText += " WITH (NOLOCK)";
}
}
}
Imports DevExpress.DataAccess.Sql
Imports System.Data
Namespace XtraReportApp
Friend Class NolockInterceptor
Inherits IDBCommandInterceptor
Public Sub CommandCreated(ByVal queryName As String, ByVal command As IDbCommand)
command.CommandText &= " WITH (NOLOCK)"
End Sub
End Class
End Namespace
using DevExpress.DataAccess.Sql;
using System;
namespace XtraReportApp {
public partial class Form1 : DevExpress.XtraEditors.XtraForm {
public Form1() {
InitializeComponent();
reportDesigner1.AddService(typeof(IDBCommandInterceptor), new NolockInterceptor());
}
private void Form1_Load(object sender, EventArgs e) {
reportDesigner1.OpenReport(new XtraReport1());
}
}
}
Imports DevExpress.DataAccess.Sql
Imports System
Namespace XtraReportApp
Partial Public Class Form1
Inherits DevExpress.XtraEditors.XtraForm
Public Sub New()
InitializeComponent()
reportDesigner1.AddService(GetType(IDBCommandInterceptor), New NolockInterceptor())
End Sub
Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs)
reportDesigner1.OpenReport(New XtraReport1())
End Sub
End Class
End Namespace
See Also