SystemDialogs.md

SystemDialogs Class

Overview

This documentation covers the standard system dialogs provided by the Autodesk.AutoCAD.Windows namespace, allowing developers to invoke native AutoCAD pickers for files, colors, and linetypes.

Namespace

Autodesk.AutoCAD.Windows

Key Classes

Class	Description
OpenFileDialog	Standard file open dialog.
SaveFileDialog	Standard file save dialog.
ColorDialog	AutoCAD Color Index (ACI) and TrueColor picker.
LinetypeDialog	Linetype selection dialog.
LayerDialog	Layer selection dialog (via internal UI or custom).

Code Examples

Example 1: Open File Dialog

using Autodesk.AutoCAD.Windows;

OpenFileDialog ofd = new OpenFileDialog(
    "Select Configuration", 
    null, 
    "xml;json", 
    "SettingsFiles", 
    OpenFileDialog.OpenFileDialogFlags.DoNotTransferRemoteFiles
);

System.Windows.Forms.DialogResult dr = ofd.ShowDialog();

if (dr == System.Windows.Forms.DialogResult.OK)
{
    string selectedFile = ofd.Filename;
    // Process file
}

Example 2: Save File Dialog

SaveFileDialog sfd = new SaveFileDialog(
    "Export Data",
    "report",
    "csv",
    "ExportFile",
    SaveFileDialog.SaveFileDialogFlags.None
);

if (sfd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
    string savePath = sfd.Filename;
}

Example 3: Color Picker

ColorDialog cd = new ColorDialog();
cd.Color = Autodesk.AutoCAD.Colors.Color.FromColorIndex(ColorMethod.ByAci, 1); // Default Red
cd.IncludeByBlockByLayer = true; // Allow ByLayer/ByBlock

if (cd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
    Autodesk.AutoCAD.Colors.Color selected = cd.Color;
    Application.DocumentManager.MdiActiveDocument.Editor.WriteMessage($"\nSelected: {selected.ColorIndex}");
}

Example 4: Linetype Picker

LinetypeDialog ltd = new LinetypeDialog();
// ltd.LinetypeId = ...; // Set default

if (ltd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
    ObjectId linetypeId = ltd.LinetypeId;
    // Apply linetype
}

Example 5: MessageBox (Standard)

// AutoCAD provides standard MessageBox integration but usually you use standard Forms/WPF
// For AutoCAD-style alert:
Application.ShowAlertDialog("Critical Error Occurred!");

Example 6: Layer State Dialog (Advanced)

// There is no simplistic "LayerDialog" class exposed directly like ColorDialog.
// Usually developers build a custom form listing layers from the database,
// or use COM interop to invoke built-in dialogs.

Example 7: Handling Dialog Results

// Dialogs return System.Windows.Forms.DialogResult
// Remember to reference System.Windows.Forms
if (result == System.Windows.Forms.DialogResult.Cancel)
{
    // User cancelled
    return;
}

Example 8: Folder Browser

// For folder selection, use standard .NET 
// System.Windows.Forms.FolderBrowserDialog
// AutoCAD does not provide a specific override for this.

Best Practices

1. Modal Context: These dialogs are modal. They block the AutoCAD UI until closed.
2. References: Requires System.Windows.Forms reference in your project.
3. UI Thread: Always show dialogs from the main UI thread.

Related Objects

• Editor
• Application

References

• Autodesk Windows Namespace