Log record changes in SQL server in an audit table

CREATE TABLE [dbo].[AuditLog](
    [AuditLogId] [int] IDENTITY(1,1) NOT NULL,
    [TableName] [varchar](100) NOT NULL,
    [AuditActionId] [char](1) NOT NULL,
    [RecordId] [varchar](100) NULL,
    [AuditDateTime] [datetime] NOT NULL,
    [UserId] [varchar](20) NOT NULL,
 CONSTRAINT [PK_AuditLog] PRIMARY KEY CLUSTERED 
(
    [AuditLogId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

CREATE TABLE [dbo].[AuditLogItem](
    [AuditLogItemId] [int] IDENTITY(1,1) NOT NULL,
    [AuditLogId] [int] NOT NULL,
    [FieldName] [varchar](100) NOT NULL,
    [OldValue] [varchar](1000) NULL,
    [NewValue] [varchar](1000) NULL,
 CONSTRAINT [PK_MT_AuditLogItem] PRIMARY KEY CLUSTERED 
(
    [AuditLogItemId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

In your DataClasses insert this code:

public partial class YourDataClassesDataContext : System.Data.Linq.DataContext 
{ 
    #region " RossiniAudit "
    public override void SubmitChanges(System.Data.Linq.ConflictMode failureMode) 
    { 
        var changeSet = this.GetChangeSet(); 
        foreach (var update in changeSet.Updates) 
        { 
            if (update as AuditLogItem == null && update as AuditLog == null) 
            { 
                var table = this.GetTable(update.GetType()); 
                var a = this.Mapping.GetTable(update.GetType()); 
                var b = a.RowType.DataMembers.SingleOrDefault(x => x.IsPrimaryKey); 
                var PrimaryKey = update.GetType().GetProperty(b.Name).GetValue(update, null); 
                var modifications = table.GetModifiedMembers(update); 
                AuditLog header = new AuditLog(); 
                AuditLogs.InsertOnSubmit(header); 
                header.UserId = UserLoggedOn; 
                header.AuditDateTime = DateTime.Now; 
                header.TableName = update.GetType().Name; 
                header.RecordId = PrimaryKey.ToString(); 
                header.AuditActionId = 'E'; 
                
                foreach (var modification in modifications) 
                { 
                    AuditLogItem log = new AuditLogItem(); 
                    log.FieldName = modification.Member.Name; 
                    log.OldValue = modification.OriginalValue.ToString(); 
                    log.NewValue = modification.CurrentValue.ToString(); 
                    header.AuditLogItems.Add(log);
                } 
            } 
        } 
        
        base.SubmitChanges(failureMode); 
    } 
    
    public string UserLoggedOn 
    { 
        get { return HttpContext.Current.User.Identity.Name; } 
    } 
    #endregion 
}