User Commands

This page lets you create your own user-defined commands.

User-defined commands are pre-defined commands that you create yourself. Effectively it's like creating a toolbar button with your own function on it, but instead of a button on a toolbar it's a command in the command list that other buttons or menus can use just like an internal command.

Use the toolbar to create and manage your user commands.

Editing a user command

Editing a user command is similar to editing a normal toolbar button, although there are a few specific fields for user commands:

• Name: This is the raw name of the command - it's the name that you need to use to run the command from buttons and menus.

• Label: This is the default label of the command. If you drag your command from the Commands tab and drop it on a toolbar, the created button will have this as its label (which can of course then be edited).

• Description: This becomes the default tooltip of the button when you drag the command from the Commands tab.

• Template: This specifies the argument template for the command - see below for more details.

• Hide from Commands menu: The command won't be displayed in drop-down command lists. This lets you create user commands that you can still use in buttons and hotkeys (or, for example, on a Preferences page like Folder Tree Selection Events), but they won't clutter up the command list.

Argument templates

If you want to be able to pass arguments to your user command you need to give it an argument template. This uses the same syntax as for internal Opus commands.

In the above example, we only want a single string value. The argument has been given the name EXT in the template field. This is not the value of the argument (that doesn't exist until something uses this user command), but the name of the argument.

The function for the user command, Select *.&EXT&, calls the internal Select command, passing it a wildcard string that is built from the supplied EXT parameter. The argument name is supplied in the function definition surrounded by ampersands (& characters) which indicates to Opus that the value of that argument is to be inserted in the command line.

You could use this example command from a toolbar button like so:

Command line:	Select_Files_Of_Type txt
Runs:	Select *.txt

More complex templates

In the above example, EXT is a string argument and so the value supplied is passed through unchanged to the user command, but for boolean options the behaviour is different. For example, consider the following user command:

Name:	ExampleCmd
Template:	EXAMPLE1/S,EXAMPLE2/O
Function:	C:\DummyProgram.exe &EXAMPLE1& &EXAMPLE2&

The ExampleCmd user command will run the C:\DummyProgram.exe program when it's invoked. Its template has two boolean options:

• EXAMPLE1: a straight switch argument, either on or off.

• EXAMPLE2: an option switch argument, which can be off, on or have a string value supplied.

By default, a switch argument will insert the value 1 when it is set, and 0 when it isn't. For example, the following use of the user command would produce the following command line for DummyProgram:

Command line:	ExampleCmd EXAMPLE1
Runs:	C:\DummyProgram.exe 1 0

However, you can use the &..& insert to specify the actual strings that are passed through for that argument. For example:

Function:	C:\DummyProgram.exe &EXAMPLE1:yes:no& &EXAMPLE2:one:two&
Command line:	ExampleCmd EXAMPLE2
Runs:	C:\DummyProgram.exe no one

For option switch (/O) arguments this only applies if the argument has been used as a switch, and not to provide a string value - if a string value is supplied instead, it is passed through unchanged. For example:

Command line:	ExampleCmd EXAMPLE1 EXAMPLE2=test
Runs:	C:\DummyProgram.exe yes test

Your template can also specify a list of values for an option switch which will then be shown in the drop-down list in the command editor, making it easy to pick the value for the argument. If you use this, you can also specify a default value, which will be passed through if a value is not given for the option. Consider the following template and the two example uses:

Name:	ExampleCmd
Template:	EXAMPLE/O[<default>,one,two,three]
Function:	C:\DummyProgram.exe &EXAMPLE&
Command line:	ExampleCmd EXAMPLE
Runs:	C:\DummyProgram.exe default
Command line:	ExampleCmd EXAMPLE=two
Runs:	C:\DummyProgram.exe two

Conditional testing

You can use the @if: command modifier to test the value of user command arguments to introduce simple conditional behaviour to your user commands (without resorting to scripting). For example:

@if:&&EXAMPLE&&=one
C:\Program1.exe
@if:&&EXAMPLE&&=two
C:\Program2.exe
@if:else
C:\DummyProgram.exe

You can also use the Arg() function in the evaluator to access command line arguments from evaluator code inside a user command. For example:

@if:=(Arg("NAME")=="jon")
echo Hi Jon!
@if:else
echo Who are you?