ArcGIS Pro 2.6 API Reference Guide
RemoveStyle Method
Example 

ArcGIS.Desktop.Mapping Namespace > StyleHelper Class : RemoveStyle Method
The current ArcGIS Pro project from which the style has to be removed.
Name of a core ArcGIS Pro style or the full path to a style file (.stylx) on disk that has to be removed from the current project.
Removes the specified style from the current project. This method must be called on the MCT. Use QueuedTask.Run.
Syntax
public static void RemoveStyle( 
   Project project,
   string styleName
)
Public Shared Sub RemoveStyle( _
   ByVal project As Project, _
   ByVal styleName As String _
) 

Parameters

project
The current ArcGIS Pro project from which the style has to be removed.
styleName
Name of a core ArcGIS Pro style or the full path to a style file (.stylx) on disk that has to be removed from the current project.
Exceptions
ExceptionDescription
This method must be called within the lambda passed to QueuedTask.Run
Example
//For ArcGIS Pro system styles, just pass in the name of the style to remove from the project
await QueuedTask.Run(() => StyleHelper.RemoveStyle(Project.Current, "3D Vehicles"));

//For custom styles, pass in the full path to the style file on disk
string customStyleToAdd = @"C:\Temp\CustomStyle.stylx";
await QueuedTask.Run(() => StyleHelper.RemoveStyle(Project.Current, customStyleToAdd));
Requirements

Target Platforms: Windows 10, Windows 8.1, Windows 7

See Also

Reference

StyleHelper Class
StyleHelper Members