Working with lists in PowerPoint Library

11 Apr 202324 minutes to read

Creating a simple list

Essential Presentation allows you to create simple and multi-level lists that make the content easier for reading. In PowerPoint, Presentation lists consists of the following types

1. Numbered list
2. Bulleted list
3. Picture list

Numbered List

The following code example illustrates how to create a numbered list:

C# [Cross-platform]

//Creates a new Presentation instance.
IPresentation pptxDoc = Presentation.Create();
//Adds a blank slide into the Presentation
ISlide slide = pptxDoc.Slides.Add(SlideLayoutType.Blank);
// Adds a textbox to hold the list
IShape textBoxShape = slide.AddTextBox(65, 140, 410, 270);
//Adds a new paragraph with the text in the left hand side textbox.
IParagraph paragraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.");
//Sets the list type as Numbered
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the starting value as 1
paragraph.ListFormat.StartValue = 1;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located in Washington with 290 employees, several regional sales teams are located throughout their market base.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
// Sets the hanging value
paragraph.FirstLineIndent = -20;
// Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Save the PowerPoint Presentation as stream
FileStream outputStream = new FileStream("Sample.pptx", FileMode.Create);
pptxDoc.Save(outputStream);
//Closes the Presentation
pptxDoc.Close();

C# [Windows-specific]

//Creates a new Presentation instance.
IPresentation pptxDoc = Presentation.Create();
//Adds a blank slide into the Presentation
ISlide slide = pptxDoc.Slides.Add(SlideLayoutType.Blank);
//Adds a textbox to hold the list
IShape textBoxShape = slide.AddTextBox(65, 140, 410, 270);
// Adds a new paragraph with the text in the left hand side textbox.
IParagraph paragraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.");
//Sets the list type as Numbered
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the starting value as 1
paragraph.ListFormat.StartValue = 1;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located in Washington with 290 employees, several regional sales teams are located throughout their market base.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Saves the Presentation to the file system.
pptxDoc.Save("Sample.pptx");
Process.Start("Sample.pptx");
//Closes the Presentation
pptxDoc.Close();

VB.NET [Windows-specific]

'Creates a new Presentation instance.
Dim pptxDoc As IPresentation = Presentation.Create()
'Adds the slide into the Presentation
Dim slide As ISlide = pptxDoc.Slides.Add(SlideLayoutType.Blank)
'Adds a textbox to hold the list
Dim textBoxShape As IShape = slide.AddTextBox(65, 140, 410, 270)
'Adds a new paragraph with the text in the left hand side textbox.
Dim paragraph As IParagraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.")
'Sets the list type as Numbered
paragraph.ListFormat.Type = ListType.Numbered
'Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod
'Sets the starting value as 1
paragraph.ListFormat.StartValue = 1
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100
'Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.")
'Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Numbered
'Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100
'Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located Washington with 290 employees, several regional sales teams are located throughout their market base.")
'Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Numbered
'Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100
'Saves the Presentation to the file system.
pptxDoc.Save("Sample.pptx")
Process.Start("Sample.pptx")
'Closes the Presentation
pptxDoc.Close()

You can download a complete working sample from GitHub.

Bulleted list

The following code example demonstrates how to create a simple bulleted list.

C# [Cross-platform]

//Creates a new Presentation instance.
IPresentation pptxDoc = Presentation.Create();
//Adds the slide into the Presentation
ISlide slide = pptxDoc.Slides.Add(SlideLayoutType.Blank);
// Adds a textbox to hold the list
IShape textBoxShape = slide.AddTextBox(65, 140, 410, 250);
//Adds a new paragraph with the text in the left hand side textbox.
IParagraph paragraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Bulleted;
//Sets the bullet character for this list
paragraph.ListFormat.BulletCharacter = Convert.ToChar(183);
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the font for the bullet character
paragraph.ListFormat.FontName = "Symbol";
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Bulleted;
//Sets the bullet character for this list
paragraph.ListFormat.BulletCharacter = Convert.ToChar(183);
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the font for the bullet character
paragraph.ListFormat.FontName = "Symbol";
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;            
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located in Washington with 290 employees, several regional sales teams are located throughout their market base.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Bulleted;
//Sets the bullet character for this list
paragraph.ListFormat.BulletCharacter = Convert.ToChar(183);
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the font of the bullet character
paragraph.ListFormat.FontName = "Symbol";
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Save the PowerPoint Presentation as stream
FileStream outputStream = new FileStream("Sample.pptx", FileMode.Create);
pptxDoc.Save(outputStream);
//Closes the Presentation
pptxDoc.Close();

C# [Windows-specific]

//Creates a new Presentation instance.
IPresentation pptxDoc = Presentation.Create();
//Adds the slide into the Presentation
ISlide slide = pptxDoc.Slides.Add(SlideLayoutType.Blank);
//Adds a textbox to hold the list
IShape textBoxShape = slide.AddTextBox(65, 140, 410, 250);
// Adds a new paragraph with the text in the left hand side textbox.
IParagraph paragraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Bulleted;
//Sets the bullet character for this list
paragraph.ListFormat.BulletCharacter = Convert.ToChar(183);
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the font for the bullet character
paragraph.ListFormat.FontName = "Symbol";
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Bulleted;
//Sets the bullet character for this list
paragraph.ListFormat.BulletCharacter = Convert.ToChar(183);
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the font for the bullet character
paragraph.ListFormat.FontName = "Symbol";
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;            
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located in Washington with 290 employees, several regional sales teams are located throughout their market base.");
//Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Bulleted;
//Sets the bullet character for this list
paragraph.ListFormat.BulletCharacter = Convert.ToChar(183);
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the font of the bullet character
paragraph.ListFormat.FontName = "Symbol";
//Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100;
//Saves the Presentation to the file system.
pptxDoc.Save("Sample.pptx");
Process.Start("Sample.pptx");
//Closes the Presentation
pptxDoc.Close();

VB.NET [Windows-specific]

'Creates a new Presentation instance.
Dim pptxDoc As IPresentation = Presentation.Create()
'Adds the slide into the Presentation
Dim slide As ISlide = pptxDoc.Slides.Add(SlideLayoutType.Blank)
'Adds a textbox to hold the list
Dim textBoxShape As IShape = slide.AddTextBox(65, 140, 410, 250)
'Adds a new paragraph with the text in the left hand side textbox.
Dim paragraph As IParagraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.")
'Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Bulleted
'Sets the bullet character for this list
paragraph.ListFormat.BulletCharacter = Convert.ToChar(183)
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
'Sets the font for the bullet character
paragraph.ListFormat.FontName = "Symbol"
'Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100
'Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.")
'Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Bulleted
'Sets the bullet character for this list
paragraph.ListFormat.BulletCharacter = Convert.ToChar(183)
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
'Sets the font for the bullet character
paragraph.ListFormat.FontName = "Symbol"
'Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100
'Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located in Washington with 290 employees, several regional sales teams are located throughout their market base.")
'Sets the list type as bulleted
paragraph.ListFormat.Type = ListType.Bulleted
'Sets the bullet character for this list
paragraph.ListFormat.BulletCharacter = Convert.ToChar(183)
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
'Sets the font of the bullet character
paragraph.ListFormat.FontName = "Symbol"
'Sets the bullet character size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 100
'Saves the Presentation to the file system.
pptxDoc.Save(""Sample.pptx"")
Process.Start(""Sample.pptx"")
'Closes the Presentation
pptxDoc.Close()

You can download a complete working sample from GitHub.

Picture List

The following code example demonstrates how to create a simple picture list.

C# [Cross-platform]

//Creates a new Presentation instance.
IPresentation pptxDoc = Presentation.Create();
//Adds the slide into the Presentation
ISlide slide = pptxDoc.Slides.Add(SlideLayoutType.Blank);
//Adds a textbox to hold the list
IShape textBoxShape = slide.AddTextBox(65, 140, 410, 270);
//Adds a new paragraph with the text in the left hand side textbox.
IParagraph paragraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.");
//Sets the list type as Numbered
paragraph.ListFormat.Type = ListType.Picture;
//Sets the image for the list.
paragraph.ListFormat.Picture(pictureStream);
//Sets the picture size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 150;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.");
//Sets the list type as picture
paragraph.ListFormat.Type = ListType.Picture;
//Sets the image for the list.
paragraph.ListFormat.Picture(pictureStream);
//Sets the picture size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 150;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Save the PowerPoint Presentation as stream
FileStream outputStream = new FileStream("Sample.pptx", FileMode.Create);
pptxDoc.Save(outputStream);
//Closes the Presentation
pptxDoc.Close();

C# [Windows-specific]

//Creates a new Presentation instance.
IPresentation pptxDoc = Presentation.Create();
//Adds the slide into the Presentation
ISlide slide = pptxDoc.Slides.Add(SlideLayoutType.Blank);
// Adds a textbox to hold the list
IShape textBoxShape = slide.AddTextBox(65, 140, 410, 270);
// Adds a new paragraph with the text in the left hand side textbox.
IParagraph paragraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.");
//Sets the list type as Numbered
paragraph.ListFormat.Type = ListType.Picture;
//Sets the image for the list.
paragraph.ListFormat.Picture(new MemoryStream(Syncfusion.Drawing.Image.FromFile("Image.png").ImageData));
//Sets the picture size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 150;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
// Sets the hanging value
paragraph.FirstLineIndent = -20;
//Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.");
//Sets the list type as picture
paragraph.ListFormat.Type = ListType.Picture;
//Sets the image for the list.
paragraph.ListFormat.Picture(new MemoryStream(Syncfusion.Drawing.Image.FromFile("Image.png").ImageData));
//Sets the picture size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 150;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Saves the Presentation to the file system.
pptxDoc.Save("Sample.pptx");
//Closes the Presentation
pptxDoc.Close();

VB.NET [Windows-specific]

'Creates a new Presentation instance.
Dim pptxDoc As IPresentation = Presentation.Create()
'Adds the slide into the Presentation
Dim slide As ISlide = pptxDoc.Slides.Add(SlideLayoutType.Blank)
'Adds a textbox to hold the list
Dim textBoxShape As IShape = slide.AddTextBox(65, 140, 410, 270)
'Adds a new paragraph with the text in the left hand side textbox.
Dim paragraph As IParagraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.")
'Sets the list type as Numbered
paragraph.ListFormat.Type = ListType.Picture
'Sets the image for the list.
paragraph.ListFormat.Picture(New MemoryStream (Syncfusion.Drawing.Image.FromFile("Image.png").ImageData))
'Sets the picture size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 150
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Adds another paragraph with the text in the left hand side textbox.
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.")
'Sets the list type as picture
paragraph.ListFormat.Type = ListType.Picture
'Sets the image for the list.
paragraph.ListFormat.Picture(New MemoryStream (Syncfusion.Drawing. Image.FromFile("Image.png").ImageData))
'Sets the picture size. Here, 100 means 100% of its text. Possible values can range from 25 to 400.
paragraph.ListFormat.Size = 150
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Saves the Presentation to the file system.
pptxDoc.Save("Sample.pptx")
'Closes the Presentation
pptxDoc.Close()

You can download a complete working sample from GitHub.

Creating a Multilevel List

You can create a multi-level list by setting the indentation levels. By default, the level begins at 0 and increments by 1 for each level. A list can be incremented or decremented from levels 0 to 8 as like Microsoft PowerPoint.

The following code example demonstrates how to create a multilevel list.

C# [Cross-platform]

//Creates a new Presentation instance.
IPresentation pptxDoc = Presentation.Create();
//Adds the slide into the Presentation
ISlide slide = pptxDoc.Slides.Add(SlideLayoutType.Blank);
//Adds a textbox to hold the bulleted list
IShape textBoxShape = slide.AddTextBox(65, 140, 410, 250);
//Adds paragraph to the textbox
IParagraph paragraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.");
//Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the starting value as 1
paragraph.ListFormat.StartValue = 1;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
// Sets the hanging value
paragraph.FirstLineIndent = -20;
//Adds paragraph to the textbox
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.");
//Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as lower case alphabet following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.AlphaLcPeriod;
//Sets the list level as 2
paragraph.IndentLevelNumber = 2;
//Sets the hanging value
paragraph.FirstLineIndent = -20;         
//Add paragraph to the textbox
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located Washington with 290 employees, several regional sales teams are located throughout their market base.");
//Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as roman number lower casing following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.RomanLcPeriod;
//Sets the list level as 3
paragraph.IndentLevelNumber = 3;
//Sets the hanging value
paragraph.FirstLineIndent = -20;         
//Adds paragraph to the textbox
paragraph = textBoxShape.TextBody.AddParagraph("These subcomponents are shipped to another location for final product assembly");
//Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered;
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;         
//Save the PowerPoint Presentation as stream
FileStream outputStream = new FileStream("MultiLevelList.pptx", FileMode.Create);
pptxDoc.Save(outputStream);
//Closes the Presentation
pptxDoc.Close();

C# [Windows-specific]

//Creates a new Presentation instance.
IPresentation pptxDoc = Presentation.Create();
//Adds the slide into the Presentation
ISlide slide = pptxDoc.Slides.Add(SlideLayoutType.Blank);
//Adds a textbox to hold the bulleted list
IShape textBoxShape = slide.AddTextBox(65, 140, 410, 250);
//Adds paragraph to the textbox
IParagraph paragraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.");
//Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the starting value as 1
paragraph.ListFormat.StartValue = 1;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Adds paragraph to the textbox
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.");
//Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as lower case alphabet following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.AlphaLcPeriod;
//Sets the list level as 2
paragraph.IndentLevelNumber = 2;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Add paragraph to the textbox
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located Washington with 290 employees, several regional sales teams are located throughout their market base.");
//Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered;
//Sets the numbered style (list numbering) as roman number lower casing following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.RomanLcPeriod;
//Sets the list level as 3
paragraph.IndentLevelNumber = 3;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Adds paragraph to the textbox
paragraph = textBoxShape.TextBody.AddParagraph("These subcomponents are shipped to another location for final product assembly");
//Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered;
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod;
//Sets the list level as 1
paragraph.IndentLevelNumber = 1;
//Sets the hanging value
paragraph.FirstLineIndent = -20;
//Saves the Presentation to the file system.
pptxDoc.Save("MultiLevelList.pptx");
//Closes the Presentation
pptxDoc.Close();

VB.NET [Windows-specific]

'Creates a new Presentation instance.
Dim pptxDoc As IPresentation = Presentation.Create()
'Adds the slide into the Presentation
Dim slide As ISlide = pptxDoc.Slides.Add(SlideLayoutType.Blank)
'Adds a textbox to hold the bulleted list
Dim textBoxShape As IShape = slide.AddTextBox(65, 140, 410, 250)
'Adds paragraph to the textbox
Dim paragraph As IParagraph = textBoxShape.TextBody.AddParagraph("AdventureWorks Cycles, the fictitious company on which the AdventureWorks sample databases are based, is a large, multinational manufacturing company.")
'Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered
'Sets the numbered style (list numbering) as Arabic number following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod
'Sets the starting value as 1
paragraph.ListFormat.StartValue = 1
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
' Sets the hanging value
paragraph.FirstLineIndent = -20
'Adds paragraph to the textbox
paragraph = textBoxShape.TextBody.AddParagraph("The company manufactures and sells metal and composite bicycles to North American, European and Asian commercial markets.")
'Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered
'Sets the numbered style (list numbering) as lower case alphabet following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.AlphaLcPeriod
'Sets the list level as 2
paragraph.IndentLevelNumber = 2
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Adds paragraph to the textbox
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located Washington with 290 employees, several regional sales teams are located throughout their market base.")
'Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered
'Sets the numbered style (list numbering) as roman number lower casing following by period.
paragraph.ListFormat.NumberStyle = NumberedListStyle.RomanLcPeriod
'Sets the list level as 3
paragraph.IndentLevelNumber = 3
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Adds paragraph to the textbox
paragraph = textBoxShape.TextBody.AddParagraph("While its base operation is located in Washington with 290 employees, several regional sales teams are located throughout their market base.")
'Sets the list type as Numbered list
paragraph.ListFormat.Type = ListType.Numbered
paragraph.ListFormat.NumberStyle = NumberedListStyle.ArabicPeriod
'Sets the list level as 1
paragraph.IndentLevelNumber = 1
'Sets the hanging value
paragraph.FirstLineIndent = -20
'Saves the Presentation to the file system.
pptxDoc.Save("MultiLevelList.pptx")
'Closes the Presentation
pptxDoc.Close()

You can download a complete working sample from GitHub.

The above code example generates a multi-level list in Presentation as follows.