const
//Image constants- the image locations in the ImageList
COMPUTERIMG= 0;
LOGIMG= 2;
ERRORIMG= 3;
WARNINGIMG= 4;
INFOIMG= 5;
AUDITIMG= 6;

type
stringarray= array of string;


// In the TWinForm class of the new form
private
strSelEvtLogName: string;
strSelComputerName: string;
procedure AddComputer(mytreeview: TreeView; computername: string);
procedure AppendLogMessage(myrichtextbox: RichTextBox; logname: string;
computername: string; index: Integer);
procedure DisplayLogEntries(mylistview: ListView; logname: string;
computername: string);
function GetEventLogNames(computername: string):stringarray;

// The class code
procedure TWinForm.DisplayLogEntries(mylistview: ListView; logname,
computername: string);
var
e: EventLog;
entry: EventLogEntry;
listitem: ListViewItem;
oldCursor: System.Windows.Forms.Cursor;
begin
e:= EventLog.Create(logname, computername);
oldCursor:= Cursor;
Cursor:= Cursors.WaitCursor;

mylistview.BeginUpdate;
mylistview.Items.Clear;

for entry in e.Entries do
begin
// Set the image index for the entry type
Case entry.EntryType of
EventLogEntryType.Error: begin // 1
listitem:= mylistview.Items.Add('Error');
listitem.ImageIndex:= ERRORIMG;
end;
EventLogEntryType.FailureAudit: begin // 16
listitem:= mylistview.Items.Add('Failure Audit');
listitem.ImageIndex:= AUDITIMG;
end;
EventLogEntryType.Information: begin // 4
listitem:= mylistview.Items.Add('Information');
listitem.ImageIndex:= INFOIMG;
end;
EventLogEntryType.SuccessAudit: begin // 8
listitem:= mylistview.Items.Add('Success Audit');
listitem.ImageIndex:= AUDITIMG;
end;
EventLogEntryType.Warning: begin // 2
listitem:= mylistview.Items.Add('Warning');
listitem.ImageIndex:= WARNINGIMG;
end;
end;

listitem.SubItems.Add(entry.TimeGenerated.ToLocalTime.ToString);
listitem.SubItems.Add(entry.Source);
listitem.SubItems.Add(entry.Category);

// The EventID property has been deprecated. in 2.0
listitem.SubItems.Add(entry.EventID.ToString);

// Note: The InstanceId property is new in the .NET Framework version 2.0.
//listitem.SubItems.Add(entry.InstanceId);

listitem.SubItems.Add(entry.UserName);
listitem.SubItems.Add(entry.MachineName);

//Remarks: Index is not necessarily zero-based. I love stuff like this
listitem.SubItems.Add(entry.Index.ToString);
end;

mylistview.EndUpdate;
Cursor:= oldCursor;

end;

procedure TWinForm.AddComputer(mytreeview: TreeView; computername: string);
var
strNames: stringarray;
strMy: string;
computernode,lognode: TreeNode;
begin
// Get a list of the event logs for a computer
strNames:= GetEventLogNames(computername);

computerNode:= mytreeview.Nodes.Add(computername);
computerNode.ImageIndex:= COMPUTERIMG;
for strMy in strNames do
begin
logNode:= computerNode.Nodes.Add(strMy);
logNode.ImageIndex:= LOGIMG;
logNode.SelectedImageIndex:= logNode.ImageIndex;
end;
end;

procedure TWinForm.AppendLogMessage(myrichtextbox: RichTextBox; logname,
computername: string; index: Integer);
var
e: EventLog;
entry: EventLogEntry;
begin
e:= EventLog.Create(logname, computername);
entry:= e.Entries.Item[index];
myrichtextbox.AppendText(entry.Message);
end;

function TWinForm.GetEventLogNames(computername: string):stringarray;
var
c: Integer;
eventlogs: array of EventLog;
e: EventLog;
strNames: stringarray;
begin
c:= 0;
eventlogs:= EventLog.GetEventLogs(computername);

// Resize the array to number of eventlog names
SetLength(strNames, High(eventlogs)+1);

// Loop through the eventlogs and get the names
for e in eventLogs do
begin
strNames[c]:= e.LogDisplayName;
c:= c + 1;
end;

result:= strNames;
end;

procedure TWinForm.TreeView1_AfterSelect(sender: System.Object; e: System.Windows.Forms.TreeViewEventArgs);
var
myTreeView: TreeView;
myNode: TreeNode;
myParentNode: TreeNode;
begin
if sender is TreeView then
begin
myTreeView:= sender as TreeView;
myNode:= myTreeView.SelectedNode;
if (myNode.Parent <> Nil) then
begin
myParentNode:= myTreeView.SelectedNode.Parent;
strSelEvtLogName:= myNode.Text;
strSelComputerName:= myParentNode.Text;
DisplayLogEntries(ListView1, strSelEvtLogName, strSelComputerName);
end
else
begin
ListView1.Items.Clear;
end;
end;
end;

procedure TWinForm.ListView1_SelectedIndexChanged(sender: System.Object; e: System.EventArgs);
var
myItem: ListViewItem;
mySubItem: ListViewItem.ListViewSubItem;
index: Integer;
begin
RichTextBox1.Clear;
for myItem in ListView1.SelectedItems do
begin
index:= myItem.Index;
//mySubItem:= myItem.SubItems.Item[7];
//index:= Convert.ToInt32(mySubItem.Text) - 1;
AppendLogMessage(RichTextBox1, strSelEvtLogName, strSelComputerName, index);
end;
end;

procedure TWinForm.TWinForm_Load(sender: System.Object; e: System.EventArgs);
begin
// Add information for the local computer
AddComputer(TreeView1, SystemInformation.ComputerName);
// Expand display
TreeView1.ExpandAll;
end;