We recommend using Visual Studio 2017

ReportViewerWebPart.DocumentMapMode Property

Gets or sets an enumeration value that indicates the visibility mode of the document map area.

Namespace:  Microsoft.ReportingServices.SharePoint.UI.WebParts
Assembly:  Microsoft.ReportingServices.SharePoint.UI.WebParts (in Microsoft.ReportingServices.SharePoint.UI.WebParts.dll)

public CollapsibleDisplayMode DocumentMapMode { get; set; }

This property can be configured using the Document Map list box in the tool pane of the Web-based Web Part design user interface.

Community Additions