Run External Programs via Open With...

Sometimes you need to access an external program to view a file or perform additional tasks beyond what Markdown Monster can provide. There are a couple of ways you can access external programs and optionally reference the currently open or selected file:

  • Standard Open With... Shell Functionality
  • Adding your own External Programs

Both of these are available on:

  • The Editor and Tab Context Menus via Open...
  • The Folder Browser's File or Folder Context Menu via Open...

Standard Open With Behavior

The Open With functionality uses the standard Windows Open With... dialog that based on a file name shows associated applications that Windows knows about:

This option is available via:

  • Active Document Context Menu
  • Active Tab Context Menu
  • Folder Browser Context Menu

Here's how you get to the option on the context menu (Folder Browser Version):

Custom External Programs

In addition to the default Windows behavior you can also add your own External Programs and show them on the Open With context menu, just below the default Open... menu option.

Configuring External Programs

External Programs have to be configured manually in the MarkdownMonster.json file, by specifying an array of external programs. You can access this file via the menu:

  • Tools -> Settings
  • Search for External Programs
  • Click the link button to edit in markdownmonster.json

External Editing of MarkdownMonster.json

If you make changes to MarkdownMonster.json outside of the Markdown Monster editor, make sure that Markdown Monster is not running before saving. Otherwise MM will overwrite your changes before they are used. Using the internal editor detects changes to the configuration file and reloads the configuration settings upon save, so changes are preserved.

Here's what the ExternalPrograms configuration in markdownmonster.json looks like with some examples:

"ExternalPrograms": [
    "Name": "Open in VS Code",
    "Executable": "C:\\Program Files\\Microsoft VS Code\\Code.exe",
    "Args": "\"{0}:{1}:{2}\" -g",
    "SaveBeforeActivation": true,
    "Extensions": "TEXT,FOLDER"
    "Name": "Open in Paint.NET",
    "Executable": "C:\\Program Files\\\\paintdotnet.exe",
    "Args": "{0}",
    "Extensions": "IMAGE"
	"Name": "Open in SmartGit",
    "Executable": "C:\\Program Files\\SmartGit\\bin\\smartgit.exe",
    "SaveBeforeActivation": false,
    "Args": "{0}",
    "Extensions": ""
    "Name": "Open in Online SVG Editor 2",
    "Executable": "",
    "Args": "{ToClipboardText}",
    "SaveBeforeActivation": false,
    "Extensions": ".svg"

ExternalPrograms is the top level array that holds a list of programs. MM Adds a VS Code and Paint.NET if they are available by default.

Each program specifies a number of parameters:

  • Name
    This is the display name of the program that is displayed in the Context menu

  • Executable
    The full path to the executable that is to be launched. The file has to exist. Can also be an HTTP Url.

    Both Executable and Args expand embedded environment variables using %variable% syntax.

  • Args
    Command line arguments to pass to the application. There are a number of expansions that can be used

    • {0} - Current selected item, the active file or the folder browser selection
    • {1} - Current Line Number - only applies for the Active Document Context Menu
    • {2} - Current Cursor Column - only applies to the Active Document Context Menu
    • {CurrentFile} - Explicitly specifies the current file
    • {CurrentFolder} - Explicitly specifies the current folder
    • {ToClipBoardText} - If specified adds file content to the clipboard. If the document in the editor is opened via the Editor context menus, the current document text is used. If selecting a file in the Folder Browser, the content of any text file from disk is used. This feature is useful when the external application doesn't support a file name via arguments, and it's often useful with URLs where you can later paste content into a form/page.
  • Extensions
    The Extensions list is a filter that determines whether the program is available for a given file or folder. You can optionally specify a comma delimited list of file extensions that this program can be applied to.

    To specify a list of extensions you can use: .md,.mkdown,.txt

    In addition you can also use several special parameters you can specify in addition to extensions:

    • TEXT - Any Text files
    • IMAGE - Any Image Files
    • FOLDER - Any olders

    You can add one or more external programs that can be run from the active document in the editor or the selected file or folder in the folder browser.

    If you leave the extension list empty, the program is always shown on the Open With... list.

  • SaveBeforeActivation
    If true saves the active document before activation when using on the active document without prompting. The default behavior on a dirty document prompts you to save - with this flag set to true the file is immediately saved. Note that Untitled documents always prompt to save the file first and if you don't save, edit a temporary file that is deleted.

Dedicated Image Viewer and Editor

Note that MM has a configuration for dedicated image viewer and image editor which is configured separately in the MM configuration. These values - if set - are used for the View Image and Edit Image options in various menus to preview and edit images externally. The configuration settings for this are found here or in the markdownmonster.json configuration file:

which should be your preferred way for configuring your primary image editor. External Programs allow you to add additional image editors should you need more variety for different editing/viewing scenarios.

© West Wind Technologies, 2016-2023 • Updated: 01/10/23
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